v0.3.0 — Custom instructions

Highlights

Adopts the NimbleBrain platform contract for per-bundle custom instructions (nimblebrain-docs/apps/custom-instructions). Anything saved in the new settings panel reaches the agent on every conversation turn, wrapped in <app-custom-instructions> containment in the system prompt — no per-turn re-reminding required.

Added

• app://instructions resource publishing the saved overlay; platform reads on every prompt assembly.
• set_custom_instructions(text) agent tool. Empty text clears. 8 KiB UTF-8 cap; cap rejection surfaces as a structured error rather than throwing.
• Settings panel at /settings/apps/synapse-todo-board (registered via the settings placement slot) with an inline Markdown editor, byte-aware character count, Save / Reset.
• Manifest declares permissions.filesystem: "write" (corrected from the prior "read" claim — the bundle has always written via Upjack's entity store).

Changed

• Storage helper module synapse_todo_board/instructions.py — atomic temp+rename writes, missing-file safe.

Tests

7 new cases covering round-trip, clear, byte-cap rejection, manifest publishing. 45/45 pass.

See also

• feat/custom-instructions PR #6
• Reference implementation for the app://instructions convention — first bundle to adopt.