feat(tree): add type-aware field creation in Tree view

[EMTumariscal]

Description

Adds intuitive field creation to the Tree view. Hovering a document or a nested Map row reveals an Add (+) button that opens a type-aware Add Field dialog (name + type + value input adapted to the type). On save, the field is written via the existing updateDocument flow and the tree refreshes. Scope is documents plus nested Maps; Array indices are excluded, consistent with the existing field-deletion rule.

Why: adding fields through the JSON view is possible but not intuitive, and the Table view only edits top-level fields. The Tree already models every field (including nested ones) as a node with a docId.field.nested path, so it is the natural place for this.

Type of Change

• Feature
• Bug fix
• Docs
• Refactor

AI Code Generation

AI-assisted implementation (OpenCode with Muse Spark, orchestrated ODD workflow: delegated writer sub-agent for TD-1/TD-2, human-reviewed). All commits verified with typecheck, tests, scoped lint/format. Native receipt-driven review ran on the slice (medium risk): reviewer raised 3 findings (1 BLOCKER timestamp NaN guard, 2 CRITICAL parent-path fallback and JSON-clone lossiness); the bounded correction fixed 2, the validator rejected it over the remaining BLOCKER, and the BLOCKER was then fixed as ordinary follow-up work. Review ended escalated (terminal stop) — outcome is informational only.

Related Issue

No related issue exists in the tracker; this addresses the maintainer request for intuitive field creation in Tree view.

Technical Context

• Type system: getValueType/getTypeColor in src/features/collections shared utils (String, Integer, Number, Boolean, Null, Timestamp, GeoPoint, Array, Map, Reference).
• Dialog conventions reused: MUI Dialog pattern from AddDocumentDialog/EditDialog (Ctrl+Enter, monospace inputs, Type badge); datetime-local input like TreeNodeRow/DatePopover.
• Plumbing: documentService.prepareAddData (dot-path set, duplicate/empty/dots/Array rejection, structuredClone with JSON fallback) -> TreeContext.onAddField -> CollectionTab -> updateDocument thunk.
• Follow-up fixes: hardened nested parentPath derivation in TreeNodeRow, invalid-date guard in AddFieldDialog.
• Work tracking: odd/tasks/tree-add-fields.md (shipped in this PR as the feature record).

Test Environment

• Hardware/OS: Linux (dev machine)
• App: Firestudio Electron desktop (UI change, no headless runtime harness)
• Checks (local, equivalent of CI): pnpm run lint (only 1 pre-existing warning in untouched electron/controllers/firebaseController.js), pnpm run format:check clean, pnpm run typecheck clean, pnpm run test 89/89 passing across 12 files
• Model/provider: Muse Spark via OpenCode

Evidence

• pnpm run test: Test Files 12 passed, Tests 89 passed
• pnpm run typecheck: clean (tsc --noEmit)
• Scoped ESLint + Prettier on all touched files: clean
• Commits: 3623546 AddFieldDialog, a22afac add plumbing, faac5e2 review-correction hardening, 0207f8b timestamp guard, plus docs commits

Checklist

• Ran checks locally (lint / format:check / typecheck / test) — green except one pre-existing lint warning in an untouched file
• PR is focused: only Tree-view field creation + its feature record (7 files)
• AI involvement disclosed above
• No unrelated changes bundled
• Note: slice is ~596 lines, over the 400-line budget — requesting size:exception (single cohesive feature; splitting dialog vs plumbing would not leave independently shippable slices)

Size

~596 insertions / 1 deletion across 7 files (188 lines are the ODD feature record). Requesting size:exception for a single PR.

[EMTumariscal]

Superseded by #22 — consolidated PR from EMTumariscal:develop to master bundling this change with its original description preserved. Closing per maintainer request.