fix(editor): a read-only table's rows fit their cells

A table keeps each row's height on its cells and corrects it after
layout through a transaction, which a read-only editor never applies:
in a path step, a note or a card, a cell of several lines (る, う, つ in
Tae Kim's conjugation tables) ran over its row's borders. Our fork of
the editor now sizes the rows of a read-only table in place, as it
already did the table's height (81c3006c on halkyon/win32-v6; upstream's
main has the same code).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MMm7usAo6q9ZZRoPkWjoxi
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

AGENTS.md

@@ -89,7 +89,7 @@ A spaced-repetition learning app: studysets of flashcards, reviewed on an FSRS s
 - **Material's `Card` widget clashes with the domain's `Card`**: files that need both import `material_ui` with `hide Card`.
 - **State: `flutter_bloc`, uniformly.** Blocs fold repository streams into immutable states with value equality, are provided as close to their consumer as possible, and log through one global `BlocObserver`. Why: the data layer is stream-shaped, event → state machines test without widgets, and one pattern everywhere is itself the point.
 - **Value equality comes from `equatable`**, mixed in (`with Equatable`), for models and states alike; `leancode_lint`'s `missing_equatable_props` catches a field left out of `props`.
-- **Rich text is `RichContent`** (`lib/src/core/content/`): the editor's document JSON plus a `formatVersion`, pure Dart, so models and the server can use it. `lib/src/core/editor/` converts it to and from the editor's `Document` (giving tables the decimal sizes the editor casts to: JSON from imports and archives may hold whole numbers, or none) and holds the one editing widget (`RichContentEditor`) and the one read-only renderer (`RichContentView`).
+- **Rich text is `RichContent`** (`lib/src/core/content/`): the editor's document JSON plus a `formatVersion`, pure Dart, so models and the server can use it. `lib/src/core/editor/` converts it to and from the editor's `Document` (giving tables the decimal sizes the editor casts to: JSON from imports and archives may hold whole numbers, or none; our fork of the editor fits a read-only table's rows to their cells, which upstream's leaves at their stored height) and holds the one editing widget (`RichContentEditor`) and the one read-only renderer (`RichContentView`).
   - **Blocks** beyond the editor's own (callout, spoiler, formula, image, sound, YouTube video, study button) keep their type and attributes as named in `core/content/content_blocks.dart`, which `RichContent` reads too (their text counts in `plainText`, and a video or study button isn't blank). An `EditorBlocks` lists how each type is built, which can be inserted (the format bar's Insert sheet and the desktop's `/` menu show the same list) and its typing rules; the core's are `coreBlocks`, and a feature's (the study button, `feature/study/`) reach the editors through `EditorBlocksScope`, which `PersonApp` fills, since the core can't know features. One builder serves editor and view: a block asks `editorState.editable`, and read-only shows what it is for (a spoiler hidden until revealed, a formula set, a video's play). A block taken whole mixes in `AtomicBlock` (selection, the remove button); unknown types show "needs a newer version" and stay as they are. New block types keep `formatVersion` 1: raising it would hide whole studysets and paths in older apps.
 - **Time comes from `clock.now()`** (`package:clock`), never `DateTime.now()`, in server and app. Why: scheduling, streaks and expiry are deterministic under test (`withClock`, `fakeAsync`), and because Serverpod itself reads `clock.now()` (e.g. session expiry), `withClock` controls its behaviour too.
 - **UTC for storing and sending, local time for display and day boundaries.** Serverpod sends `DateTime` as UTC and stores it in `timestamp without time zone` columns. Compare and compute in UTC; call `.toLocal()` only to display. "Due today", streaks and daily goals use the learner's **local** calendar day, computed on the client; the server never needs day boundaries.