fix(web): restore command palette navigation

[TheNaubit]

What changes

Mount the existing command palette in both the project and organization layouts so Command+K and Ctrl+K open it.

Use the sidebar's project navigation list for the palette entries and remove the organization links to pages that no longer exist. Filtering, arrow-key selection and project switching still work. The usage guide now documents the shortcut.

This is a nonbreaking UI fix. It adds no dependencies and doesn't change stored data, APIs, permissions or budgets.

Why

Closes #355

The topbar shows a shortcut that does nothing because the palette is never mounted. Its old destinations also need updating before people can use it.

Verification

I ran the checks in a local Docker Sandbox microVM, with no host directories mounted.

• All six Vitest/jsdom tests passed. They cover both layouts, existing routes, filtering, keyboard selection, organization navigation and project switching.

• Web typecheck, the production build and pnpm verify passed.

• I also checked the production build in a browser with a local API fixture that returns fixed responses. All 16 checks passed, including opening and dismissing the palette, keyboard navigation, project switching and organization pages. There were no browser errors.

• pnpm verify passes locally

• Behaviour verified beyond the test suite (say how)

• Documentation updated, or no user-facing change

[Lob26]

Heads-up: this branch predates #368, which dropped Pipeline from projectNav. Merged onto current main (b7a9212), apps/docs/docs/guides/operate-story.md conflicts and 2/6 tests in apps/web/test/command-palette.test.tsx fail:

• the sections loop still expects alpha · pipeline (L94–95);
• the ArrowDown×2 case now lands on /projects/project-a/insights instead of /projects/project-a/pipeline (L114).

The component change itself holds up — it reads projectNav, so it followed #368 on its own — so this should just be a rebase plus those two expectations.