docs: add redaction approval design

Co-Authored-By: Claude Opus 4.6 <[email protected]>

docs/plans/2026-02-20-redaction-approval-design.md

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+# Redaction Approval Design
+
+**Goal:** When a user accepts a solver result, merge left text + solution + right text into a single "approved" text object that renders persistently on the page in blue.
+
+**Architecture:** Client-side state change with a new `"approved"` status, a new canvas draw function, and re-edit support via popover reopening.
+
+## State Model
+
+**On Accept (click Accept button):**
+- `r.status` = `"approved"`
+- `r.approvedText` = merged string: `leftText + solutionText + rightText`
+- `r.solution` = `{ text, fontName, fontSize }` (solution portion only, preserved for re-editing)
+- `r.preview` = `null`
+
+**On re-click of approved redaction:**
+- Popover opens in normal analyze workflow
+- `r.preview` set to `r.solution.text` so canvas shows solution in gap
+- Previous solution text appears as first pre-selected result in solver results
+- User can change offset, font, text, and re-run solvers
+- Re-accepting overwrites `r.approvedText` with new merged text
+
+**State transitions:** `unanalyzed -> analyzed -> approved`
+- `preview` is a transient visual overlay on top of `analyzed`
+- The old `"solved"` status is removed entirely
+
+## Canvas Rendering
+
+New `drawRedactionApproved(r, isActive)`:
+- Always renders the full merged line in blue (`rgba(30, 100, 255, 0.9)`)
+- Uses font/size/offset from `r.overrides`
+- Position: `line.x + offsetX, line.y + offsetY`
+- Active: blue text + line bounding box outline
+- Inactive: blue text only, no outline
+- Replaces the old `drawRedactionSolution`
+
+Render priority in `renderCanvas()`:
+1. `r.status === "approved"` -> `drawRedactionApproved`
+2. `r.preview` -> `drawRedactionPreview`
+3. `r.status === "analyzed"` -> `drawRedactionAnalyzed`
+4. fallback -> `drawRedactionUnanalyzed`
+
+## Left Panel
+
+- Status badge: "approved" with blue styling
+- Info text: full `r.approvedText` (truncated if > 30 chars)
+
+## Export
+
+`exportAnnotations()` includes `r.approvedText` in the JSON output alongside existing `r.solution` and `r.overrides`.
+
+## Removals
+
+- Delete `"solved"` from `statusLabel()` switch
+- Delete `drawRedactionSolution()` from canvas.js
+- Remove `"solved"` references from `activateRedaction`, `redactionInfoText`, etc.