Merge remote-tracking branch 'origin/master' into feat/plan-mode

Master arrivals re-grafted onto the plan-mode surfaces:
- Package invariant runtime contracts: every package owns ./invariant —
  added the dsh-mode companion (mode/set payload validation: non-empty
  trimmed name), its unit spec, exports/peer wiring, and the mode group in
  the tsconfig invariant paths glob.
- Interception waterfalls gained an AbortSignal parameter
  (agent/prompt-submit, agent/turn-continuation) and ToolExecutionInput.signal
  became required: listeners and test dispatch updated; the exit tool now
  forwards exec.signal unconditionally.
- TUI question dialog: master's position/unanswered header layout kept,
  the plan-review detail block re-grafted between question and answers.
- LSP capability family arrived: lsp tool joins the catalog pin, dsh-lsp
  examples deps beside dsh-mode; lsp-definition snapshot refreshed with
  the mode command and modes advertisement.
- docs/architecture.md and packages/README.md regenerated tables re-grafted
  (ctx.modes row, mode package row) and condensed within word ceilings.
- examples/acp-agent cordis.yml: kept the deployment-owned plan instructions
  (incl. the conversational-agreement sentence) beside master's routed-model
  compaction comment; snapshot expected outputs refreshed keyless and noise
  fixtures restored.

packages/ui/acp/package.json

@@ -11,11 +11,16 @@
       "types": "./lib/types/index.d.ts",
       "default": "./lib/index.js"
     },
+    "./invariant": {
+      "types": "./lib/types/invariant.d.ts",
+      "default": "./lib/invariant.js"
+    },
     "./src/*": "./src/*",
     "./package.json": "./package.json"
   },
   "files": [
     "lib/index.js",
+    "lib/invariant.js",
     "lib/types/**/*.d.ts",
     "lib/types/**/*.d.ts.map",
     "src"
@@ -30,6 +35,7 @@
     "@deepseek-ai/dsh-agent": "^0.0.1",
     "@deepseek-ai/dsh-bash": "^0.0.1",
     "@deepseek-ai/dsh-commands": "^0.0.1",
+    "@deepseek-ai/dsh-invariants": "^0.0.1",
     "@deepseek-ai/dsh-llm": "^0.0.1",
     "@deepseek-ai/dsh-llm-retry": "^0.0.1",
     "@deepseek-ai/dsh-mode": "^0.0.1",