feat: add persistent dynamic panels

docs/ARCHITECTURE.md

@@ -95,7 +95,12 @@ Panel attachment is independent from session lifetime. Detaching removes a pane
 from the layout tree but retains its definition in the workspace's detached
 registry and leaves its runtime-owned process alive. Reattaching restores that
 identity without a launch. Terminating an attached or detached session is a
-separate Execute-capability operation. See decision 0010.
+separate Execute-capability operation. The GPUI slice now layers an unbounded
+panel registry above the six-surface comparison fixture. New Terminal, Browser,
+Markdown, and Review panels receive monotonic local IDs, are inserted beside
+the selection, and persist their identity, order, selection, and attachment in
+a credential-free SQLite snapshot. Each Terminal panel is keyed into the
+runtime registry by that durable panel ID. See decisions 0010 and 0011.
 
 We should evaluate, not blindly copy, WezTerm, Zellij, RMUX, tmux, and cmux. The
 first spike must compare a reusable terminal crate with a small first-party layer.

docs/BUZZ_INTEGRATION.md

@@ -6,6 +6,10 @@ Buzz is Lumbridge's first-class collaboration surface, not its control plane.
 Lumbridge remains useful offline, owns its local workspace state, and never
 requires a Buzz account to open a terminal or run an agent.
 
+Lumbridge Code engineering uses the canonical `lumbridgecode` channel on the
+cloud-1 Buzz community. Buzz is the collaboration product; Lumbridge does not
+refer to or depend on Slack.
+
 The initial integration provides:
 
 - connect an existing Buzz identity using an OS credential-store reference;

docs/TESTING.md

@@ -124,9 +124,12 @@ who already have the final cargo-watch release installed.
 - The GPUI slice tests its key-event adapter, responsive one/three/five-panel
   geometry, selected-panel windowing, per-panel 20/60/20 PTY sizing, xterm
   256-color conversion, styled-run coalescing, cursor-run boundaries, and
-  scrollback shortcut routing. It renders three independently actor-owned VT
-  sessions while three non-terminal surfaces continue their deterministic
-  background workload.
+  scrollback shortcut routing. Its panel registry tests monotonic identity,
+  insert-beside-selection, detach/reattach identity preservation, snapshot
+  validation, SQLite round-trip, and refusal to reuse a restored ID. It renders
+  an independent actor-owned VT session for every Terminal panel while the
+  original three non-terminal surfaces continue their deterministic background
+  workload.
 - `lumbridge-terminal` retains 10,000 history lines by default and tests
   framework-neutral page/top/bottom viewport movement, revision changes, and
   live-bottom no-ops without sending history-navigation bytes to the child PTY.

docs/UI_SPIKE_SCORECARD.md

@@ -90,10 +90,13 @@ fallback.
 ## Measurement semantics
 
 Both renderers retain the same all-deterministic six-surface action stream for
-comparison. GPUI now presents one, three, or five vertical panels, each with its
-own 20/60/20 context/work/decision composition, while all three terminal
-fixtures are independent actor-owned VT sessions and the three non-terminal
-surfaces keep deterministic updates running. Counters
+comparison. GPUI now layers an unbounded, SQLite-snapshotted panel registry over
+that benchmark and presents one, three, or five vertical panels, each with its
+own 20/60/20 context/work/decision composition. The Add Panel chooser creates
+Terminal, Browser, Markdown, and Review panels beside the selection or
+reattaches an existing session. Every Terminal panel receives an independent
+actor-owned VT session; the three seed non-terminal surfaces keep deterministic
+updates running. Counters
 separate external PTY batches/lines from total model updates. The GPUI footer
 reports dispatch-to-element-build p50/p95 over a bounded 256-sample window. It
 is deliberately not called key-to-present or frame-present latency: neither

docs/UX_VERTICAL_SLICE.md

@@ -20,9 +20,12 @@ decision-shelf actions, usage-detail provenance, and end-to-end platform
 accessibility/IME.
 
 Panel lifecycle is now visible in the slice: every panel has a Detach action,
-the workspace bar has Add panel, and the sidebar exposes Detached sessions for
-reattachment. The wording is deliberate because panel removal keeps its session
-alive; termination is not exposed as a visually equivalent close action.
+the workspace bar opens an Add Panel chooser for Terminal, Browser, Markdown,
+and Review, and the sidebar and chooser expose Detached sessions for
+reattachment. Created panels are inserted beside the selection and receive a
+monotonic identity persisted with their ordering and attachment state in local
+SQLite. The wording is deliberate because panel removal keeps its session alive;
+termination is not exposed as a visually equivalent close action.
 
 Screenshots for the audit are stored outside Git under
 `~/shots/2026-08/lumbridge-ui-audit/`. Accessibility and IME correctness cannot
@@ -87,7 +90,7 @@ surface rather than a hosted Lumbridge control plane.
   leaving ordinary terminal arrows and text available to the PTY.
 - `Alt+1` through `Alt+6`: focus a pane directly while leaving terminal digits
   available to the PTY.
-- `Alt+Shift+N`: add or reattach the next panel in the deterministic slice.
+- `Alt+Shift+N`: open the Add Panel chooser; `1`–`4` create a typed panel.
 - `Alt+Shift+W`: detach the selected panel while its session keeps running.
 - `Cmd+K` on macOS or `Ctrl+K` on Linux: open the command palette.
 - `Shift+PageUp/PageDown`: move the selected live terminal through retained
@@ -98,8 +101,9 @@ surface rather than a hosted Lumbridge control plane.
   separate explicit action and is never triggered by focusing the pane.
 - `Escape` closes transient UI before it changes workspace state.
 
-Every command is represented by the shared interaction model so GPUI and Floem
-receive the same state transitions and tests.
+The six seed surfaces still replay through the shared interaction model so GPUI
+and Floem retain a comparable benchmark. Dynamic product panels use the GPUI
+panel registry until that contract moves into the framework-neutral UI crate.
 
 ## Decisive workload
 

docs/decisions/0009-responsive-ultrawide-work-lanes.md

@@ -22,6 +22,7 @@ derives approximately 71 columns by 42 rows per panel.
 
 The runtime slice now owns three independent real PTYs through a pane-indexed
 session registry, one for every terminal fixture. The Markdown, browser, and
-review fixtures remain deterministic comparison surfaces. Adding arbitrary new
-terminal panels requires replacing the fixed fixture identity pool with dynamic
-pane creation; it does not require another runtime ownership design.
+review fixtures remain deterministic comparison surfaces. The GPUI product
+slice now adds arbitrary panels through a persistent dynamic identity layer;
+each additional Terminal panel is another entry in the same runtime ownership
+design. The fixed fixture remains only as the GPUI/Floem benchmark input.

docs/decisions/0010-panel-lifecycle-detach-before-terminate.md

@@ -15,12 +15,11 @@ confirmation that names the process, target machine, and any dirty or waiting
 state. Detaching the selected panel chooses its next attached sibling, falling
 back to the previous sibling. A workspace retains at least one attached panel.
 
-The add affordance has two product paths: quick activation creates the user's
-default panel beside the selection, while its menu offers Terminal, Browser,
-Markdown, Review, and Reattach running session. The deterministic UI spike uses
-six fixed fixtures, starts with five attached, and reattaches the first detached
-fixture when Add panel is activated. That fixture limit is test scaffolding, not
-a product limit.
+The add affordance opens a chooser for Terminal, Browser, Markdown, Review, and
+Reattach running session. The deterministic comparison model still uses six
+seed fixtures and starts with five attached. The GPUI slice no longer inherits
+that fixture limit: Add Panel creates a new persistent panel identity beside the
+selection or reattaches the exact detached identity without relaunching it.
 
 The typed command plane retains detached pane definitions separately from the
 layout tree. `ClosePane(Detach)` moves a definition into that registry,

docs/decisions/0011-dynamic-panels-have-persistent-local-identities.md

@@ -0,0 +1,23 @@
+# 0011: Dynamic panels have persistent local identities
+
+Status: accepted for the GPUI product slice.
+
+The six-surface fixture remains a deterministic benchmark shared with Floem; it
+is not the product's panel database. GPUI layers an unbounded workspace registry
+above it. Add Panel creates Terminal, Browser, Markdown, or Review beside the
+selected panel. Each new panel receives a monotonically increasing `PanelId`
+that is never derived from its title, position, surface, process ID, or visible
+index.
+
+The registry persists panel identity, kind, title, target, order, attachment,
+selection, and the next unused ID as one versioned, credential-free SQLite
+snapshot. Invalid snapshots fail closed to the seed layout rather than partially
+restoring aliases. SQLite never stores terminal output, credentials, private
+keys, subscription tokens, or Buzz identity secrets through this boundary.
+
+Every Terminal panel uses its `PanelId` as the runtime-registry key. Detaching
+changes only layout attachment, so the actor and PTY keep running. Reattaching
+selects the same ID. A restored in-process spike must currently launch a new PTY
+for that persisted panel because actor durability across UI process restarts
+requires the planned separate Lumbridge runtime and authenticated IPC; the UI
+does not pretend otherwise.