Collapse the three runtime bootstraps into shared session assembly

TUI and exec each hand-wired the same factories; every new runtime
dependency was a three-site edit and a drift source. Shared assembly
keeps live values behind getters so session rotation still hits the
new workdir.

Author: TheGreatAxios

CHANGELOG.md

@@ -27,6 +27,7 @@ parallel copies under `docs/` or `scripts/notes/`. At cut time: rename
 
 ### Changed
 
+- Collapse the three runtime bootstraps into shared session assembly.
 - Skywalker's prompt no longer states a hard cap of 4 workers. Fan-out width
   follows independent lanes; the runtime queues excess rather than refusing.
 - Wait/list status includes live `queued`. Resume/followup inference is admitted

docs/ARCHITECTURE.md

@@ -94,7 +94,7 @@ In TUI chat mode there is no completion gate — the session stays open across t
 ### Exec Runner (`src/exec/runner.ts`)
 
 - Product non-TUI agent path that **shares** the TUI stack (session mode, ChatDirector, toolset, permission gate, MCP, plugins, hooks, run-sink) without the OpenTUI shell
-- Bootstrap is intentionally a **forked copy** of the TUI path (not a shared factory yet). Intentional deltas vs TUI:
+- Bootstrap consumes the shared session assembly (`src/session/assemble-runtime.ts`, layered over `src/session/runtime-assembly.ts`) instead of hand-wiring a second copy. Intentional deltas vs TUI:
   - No workflow controller (`isWorkflowActive` is always false)
   - Non-interactive permission gate by default; optional stdin for `ask_operator`
 - Entry: `corbits exec "prompt"` (alias `corbits run`); `loadConfig` sets `command: "exec"`

docs/IMPLEMENTATION.md

@@ -246,7 +246,7 @@ Provider and model configuration lives in JSON settings files. The global file h
 
   On expiry the call returns a normal tool-error result ("MCP tool `<name>` timed out after `<n>`s — the server may be wedged; retry or continue without it") that the model can react to; the turn itself is never aborted. `tools.maxTimeoutMs`, if set, still caps `mcp.timeoutMs`.
 
-  Optional `sessionMode` is **deprecated**. Legacy values (`single` | `orchestrator`) may still appear on disk and load without error; resolve always returns **orchestrator**. There is no first-run mode picker and no Settings row. Both the interactive TUI (`runTUI`) and the non-TUI product path (`runExec` / `corbits exec`) are orchestrator-only. Exec bootstrap is otherwise a forked copy of the TUI path (shared stack, intentional deltas documented under Architecture → Exec Runner).
+  Optional `sessionMode` is **deprecated**. Legacy values (`single` | `orchestrator`) may still appear on disk and load without error; resolve always returns **orchestrator**. There is no first-run mode picker and no Settings row. Both the interactive TUI (`runTUI`) and the non-TUI product path (`runExec` / `corbits exec`) are orchestrator-only. Exec bootstrap consumes the same session assembly as the TUI (intentional deltas documented under Architecture → Exec Runner).
 
 - Per-repo: `.corbits/settings.json` — **selection only**, e.g. `{ "provider": "firepass", "model": "fp-small" }`. Any other key (notably `apiKey` or `baseURL`) is rejected by the loader, and the file is gitignored. It is also on the secret-guard denylist for path-keyed tools, as is the global file, so the agent cannot `read_file` its own credentials (shell references still require explicit operator approval).
 

docs/PRODUCT.md

@@ -66,7 +66,7 @@ $ corbits exec "Add JWT auth to the API"
 $ corbits run "Add JWT auth to the API"
 ```
 
-Same directors, tools, permissions, MCP, plugins, and hooks as the TUI — without the OpenTUI shell. The exec bootstrap is a deliberate fork of the TUI path (not a shared factory yet); see `docs/ARCHITECTURE.md` “Exec Runner” for intentional deltas (no workflow controller; single primary send; non-interactive permission gate). Compaction continuation matches TUI so long runs do not stall after compact. Streams assistant text to stdout for scripts and CI. Non-interactive by default: actions that need operator approval are denied unless `--dangerously-skip-permissions` is set, a persisted `/yolo` default is on, or auto mode covers them. `--dangerously-skip-permissions` still forces this process; secret-guard and authz still apply. `ask_operator` reads a single line from stdin when available.
+Same directors, tools, permissions, MCP, plugins, and hooks as the TUI — without the OpenTUI shell. Bootstrap shares `src/session/assemble-runtime.ts` with the TUI; see `docs/ARCHITECTURE.md` “Exec Runner” for intentional deltas (no workflow controller; single primary send; non-interactive permission gate). Compaction continuation matches TUI so long runs do not stall after compact. Streams assistant text to stdout for scripts and CI. Non-interactive by default: actions that need operator approval are denied unless `--dangerously-skip-permissions` is set, a persisted `/yolo` default is on, or auto mode covers them. `--dangerously-skip-permissions` still forces this process; secret-guard and authz still apply. `ask_operator` reads a single line from stdin when available.
 
 Local multi-model capability checks use this path (`bun run eval:capability`); see `evals/capability/README.md`.