chore: remove old handoff docs, plans, review reports, and task lists from rootHEADmaindev

Removed 40+ markdown files that were cluttering the repo root:
- frontend-*-handoff.md (28 files) — historical API contract handoffs, features all implemented
- backend-to-fe-handoff.md, backend-to-fe-handoff-2.md — old handoff docs
- broken-chat-repair-handoff.md — old repair handoff
- PLAN-mcp.md, PLAN-per-edit-diagnostics.md — old planning docs
- ai-review-report.md, crash-review-report.md — one-time review reports
- tasks.md, HANDOFF.md — outdated status docs (git log is the source of truth)

Kept: AGENTS.md, GLOSSARY.md, ORCHESTRATOR.md, README.md
Also: gitignored ai-review-report.md so future Gemini reviews don't commit it

1 files changed, 0 insertions, 73 deletions

diff --git a/frontend-system-prompt-handoff.md b/frontend-system-prompt-handoff.md
deleted file mode 100644
index c135145..0000000
--- a/frontend-system-prompt-handoff.md
+++ /dev/null
@@ -1,73 +0,0 @@
-# FE Courier Handoff: System Prompt Builder (Updated)
-
-> Backend→FE courier. Send to FE agent `ffe3`.
-> Supersedes the earlier `frontend-system-prompt-handoff.md` — adds `prompt:workspace_id`.
-
-## API endpoints
-
-### `GET /system-prompt` → `{ template: string }`
-Returns the current global template. When none is stored, returns the built-in default.
-
-### `PUT /system-prompt` ← `{ template: string }` → `{ template: string }`
-Set the global template. Empty string = "no system prompt". 400 if `template` missing/wrong type. 503 if service unavailable.
-
-### `GET /system-prompt/variables` → `{ variables: SystemPromptVariable[] }`
-Static catalog — always available (no service dependency). Use this to render the variable selector buttons.
-
-## Template format
-
-### Variable insertion
-```
-[type:name]
-```
-Resolves at construction time. Unknown type → blank. Non-existent variable (e.g. file not found) → blank.
-
-### Conditional blocks
-```
-[if type:name]
-  ...if variable exists...
-[else]
-  ...if not...
-[endif]
-```
-Negated:
-```
-[if !type:name]
-  ...if variable does NOT exist...
-[endif]
-```
-Nested `[if]`: supported. Multi-line: supported. Unmatched `[if]`/`[endif]`: literal text.
-
-## Available variables (updated)
-
-| Type:Name | Description | Dynamic? |
-|---|---|---|
-| `system:time` | Current time (ISO 8601) | No |
-| `system:date` | Current date (YYYY-MM-DD) | No |
-| `system:os` | Operating system | No |
-| `system:hostname` | Machine hostname | No |
-| `prompt:cwd` | Working directory | No |
-| `prompt:model` | Current model name | No |
-| `prompt:conversation_id` | Conversation ID | No |
-| `prompt:workspace_id` | Workspace identifier — lets the AI know which workspace it's in, useful when summoning agents | No |
-| `git:branch` | Current git branch | No |
-| `git:status` | Short git status | No |
-| `file:<path>` | File contents (relative to cwd, or absolute if starts `/`) | **Yes** |
-
-For `file:<path>`, allow free-text input for the path.
-
-## Caching behavior
-
-System prompt is **constructed once** (first turn of a new conversation) and **persisted**. Reused on all subsequent turns (cache-safe). Reconstructed only on **compaction**. Changing the template does NOT affect existing conversations until compacted.
-
-## Default template
-
-```
-You are a helpful coding assistant.
-
-[if file:AGENTS.md]
-[file:AGENTS.md]
-[endif]
-
-The current working directory is [prompt:cwd].
-```