Agent: undo for real, past seasons, and tools that correct the record

Six tools the live assistant kept needing and a prompt that knows about them:

- undo_change wraps RevertChangeSet(source=agent). A revert is its own change
  set, so Run reports the last one as the turn's handle when the turn changed
  nothing else — an undo-only reply keeps its "Undo this", which is now a redo.
- describe_garden takes a year: the season view (GardenFull(year)), pulled
  plops included, with removed/removedAt per group and per plop; list_years
  says which years have records. Rotation questions finally have data.
- update_planting corrects a plop's date, count, label, radius or seed lot in
  place; remove_planting, remove_plantings and clear_object take a removedAt so
  a harvest can be backdated.
- update_journal_entry / delete_journal_entry correct a note instead of
  stacking a contradicting one.
- update_garden renames/resizes/re-units a garden and rewrites its notes — and
  the notes now go into the system prompt as the gardener's standing facts, so
  "remember we're in zone 6a" persists across conversations.

describe_garden also reports the garden's notes, version and grid, which the
new tools need. Prompt, CLAUDE.md and DESIGN.md updated to match; UI step
labels for the new tools.

Co-Authored-By: Claude Fable 5 <[email protected]>

web/src/lib/agent.ts

@@ -98,6 +98,7 @@ export interface AgentStep {
 const TOOL_LABELS: Record<string, string> = {
   list_gardens: 'Looking at your gardens',
   describe_garden: 'Reading the garden',
+  list_years: 'Checking past seasons',
   list_plantings: 'Reading a bed',
   create_object: 'Adding a bed',
   move_object: 'Moving a bed',
@@ -106,6 +107,7 @@ const TOOL_LABELS: Record<string, string> = {
   place_planting: 'Planting',
   fill_region: 'Filling a bed',
   move_planting: 'Moving a plant',
+  update_planting: 'Correcting a planting',
   remove_planting: 'Pulling a plant',
   remove_plantings: 'Pulling plants',
   clear_object: 'Clearing a bed',
@@ -114,10 +116,14 @@ const TOOL_LABELS: Record<string, string> = {
   update_plant: 'Updating your catalog',
   add_journal_entry: 'Writing a journal note',
   read_journal: 'Reading the journal',
+  update_journal_entry: 'Correcting a journal note',
+  delete_journal_entry: 'Deleting a journal note',
   read_history: 'Reading the history',
+  undo_change: 'Undoing a change',
   list_seed_lots: 'Checking your seed',
   record_seed_lot: 'Recording seed',
   copy_garden: 'Copying the garden',
+  update_garden: 'Changing the garden',
 }
 
 export function describeStep(step: AgentStep): string {