● tldraw: address review — relocate snapshot store, harden concurrency, drop duplicates

  Relocate
    Move persistence out of .agent/memory/visual/ into the skill itself at
    .agent/skills/tldraw/store.py. The previous layout implied a fifth
    memory layer, but there is no lifecycle, clustering, dream-cycle, or
    recall integration — it's skill-local storage, not memory. Naming now
    matches behavior.

  Concurrency
    * JSONL mutations acquire an advisory exclusive flock on Unix and a
      process-local threading.RLock on Windows (fcntl unavailable).
    * Archive does read-modify-rewrite inside a single lock scope.
    * Atomic-write tmp names include 6 bytes of entropy so two threads
      writing the same target in the same millisecond can't race on the
      tmp file.
    * Snapshot id retries are bounded (_MAX_RESAMPLE = 8) so a degenerate
      RNG can't spin forever.

  Security
    load_snapshot / archive_snapshot validate the sid against
    ^[A-Za-z0-9_-]+$ before any os.path.join. Blocks traversal inputs
    like "../etc/passwd" at the API boundary.

  Robustness
    Malformed JSONL lines are logged to stderr and skipped rather than
    silently swallowed — the store exists to surface corruption, not hide
    it.

  Duplicates removed
    * adapters/{antigravity,claude-code}/.mcp.json and
      adapters/cursor/.cursor/mcp.json were byte-identical to
      adapters/_shared/tldraw-mcp.json. install.sh and install.ps1 now
      copy the shared file into the target per adapter.
    * Deleted .agent/skills/tldraw/KNOWLEDGE.md (placeholder) and
      adapters/claude-code/.claude/commands/tldraw.md (redundant with the
      skill).

  Gitignore
    INDEX.md, snapshots/, and snapshots.jsonl under the skill are runtime
    output — gitignored so installs start clean. The PR-local validation
    harness (test_tldraw_visual_memory.py) is also gitignored

  Tests (local)
    66/66 passing. New coverage: 16-thread concurrent snapshot writes with
    post-hoc jsonl parse + count check, malformed-line recovery.

Author: Siddharth11Roy

.agent/AGENTS.md

@@ -11,8 +11,6 @@ same memory, skills, and protocols.
 - `memory/semantic/DECISIONS.md` — past architectural choices
 - `memory/semantic/LESSONS.md` — distilled patterns (rendered from `lessons.jsonl`)
 - `memory/episodic/AGENT_LEARNINGS.jsonl` — raw experience log (top-k by salience)
-- `memory/visual/INDEX.md` — durable canvas snapshots from the tldraw skill
-  (fifth layer, opt-in via the `tldraw` feature flag)
 
 ## Review Queue (host-agent responsibility)