fix project select modal ignoring excluded folders (#2390)

[enieuwy]

The "Add to Project" modal (ProjectSelectModal) listed notes from folders set in the excludedFolders setting.

Root cause: ProjectSelectModal.getItems() never applied excludedFolders. The inline project autosuggest (FileSuggestHelper) does, through parseExcludedFolders / isPathInExcludedFolder.

Fix: apply the same two helpers from src/utils/pathExclusions.ts in getItems(), before the other filters. Added a line to docs/releases/unreleased.md as AGENTS.md asks.

Testing: added a regression case in tests/unit/modals/ProjectSelectModal.property-filter.test.ts. It fails before the fix and passes after.

• npx jest tests/unit/modals/ProjectSelectModal.property-filter.test.ts: 4 passed.
• npx eslint src/modals/ProjectSelectModal.ts: clean.
• npm run typecheck (after node generate-release-notes-import.mjs): clean.
• Related modal and suggest tests (tests/unit/modals/, FileSuggestHelper, issues 1499/1814/2069): 245 passed.
• Not tested in a live Obsidian instance.

Fixes #2390

Implemented with AI assistance (Claude, via the oh-my-pi agent harness).