feat(web): add persisted project notes sidebar

[MaximIJ]

What Changed

Adds a small persisted notes scratchpad for the active project inside the thread view.

• adds a notes.toggle keybinding command with a default Mod+Shift+E binding
• adds a notes sidebar and composer control toggle in the chat view
• persists project notes through the existing project meta update/event-sourcing flow
• adds coverage for decider, projection pipeline, snapshot query, and store syncing

Why

When working across multiple threads in the same project, it helps to keep a lightweight scratchpad for reminders, todos, and context that should survive thread switches and reloads. This keeps that context close to the conversation without overloading the prompt itself.

UI Changes

This adds a notes toggle beside the existing composer controls and opens a right-hand notes sidebar with a simple textarea.

I wasn't able to attach screenshots from the CLI environment, so this section is described rather than illustrated.

Checklist

• This PR is small and focused
• I explained what changed and why
• I included before/after screenshots for any UI changes
• I included a video for animation/interaction changes

Note

Add persisted project notes sidebar to the chat view

• Adds a resizable ProjectNotesSidebar component to the chat view with a debounced textarea that persists notes by dispatching project.meta.update commands to the server.
• Notes are stored in a new notes TEXT column on the projection_projects table (migration 16), propagated through the orchestration pipeline, and synced to the client store via mapProjectsFromReadModel.
• The sidebar can be toggled via a new desktop menu item (Cmd/Ctrl+Shift+E), the notes.toggle keybinding, a footer Notes button, or the compact composer controls menu.
• Behavioral Change: the composer footer switches to compact layout at ≤820px (up from ≤720px) to accommodate the new Notes button.

^{Macroscope summarized 26d7735.}

[coderabbitai]

Important

Review skipped

Auto reviews are disabled on this repository. Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 62166075-9b4b-49c0-84d1-65d9d35e47f7

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

• 🔍 Trigger review

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

Tip

You can enable review details to help with troubleshooting, context usage and more.

Enable the reviews.review_details setting to include review details such as the model used, the time taken for each step and more in the review comments.

[MaximIJ]

Replacing this with #1268 so the notes work lands as a single clean commit on feature/project-notes instead of the earlier iterative branch history.