feat(chrome-client): add on-page annotation indicators with bidirectional navigation

AGENTS.md

@@ -215,7 +215,7 @@ No need to explicitly document the telemetry behaviors.
   Nothing (Tailwind, DaisyUI, Mermaid, layout safety CSS) is auto-injected into artifacts; agents choose a design direction via the single-sourced `DESIGN_PRIORITY_RULE` (see AXI integration above).
   The `lavish-axi design` Mermaid snippet chooses dark or light rendering from the effective artifact page background and re-renders when a page-theme or OS appearance change alters that appearance, so do not hardcode one Mermaid theme.
 - For rendered Mermaid SVGs outside `.mermaid` containers, the injected SDK retains dependency-free viewBox pan (drag) and zoom (wheel) in explore mode, then freezes it in annotation mode so a click resolves cleanly to one node instead of panning. It enhances on load and `DOMContentLoaded` and re-runs through a throttled `MutationObserver` because Mermaid renders asynchronously and can re-render. Enhancement touches only the live SVG's `viewBox` and listeners, never the saved artifact, so the diagram still renders identically when opened directly. Node detection, label extraction, and target validation live in `src/mermaid-node.js` so they are unit-testable and shared with the server.
-- Any helper `createArtifactSdk` calls must reach the browser through `serializeModuleHelpers` in `createSdkJs`, which turns every export of a shared module (`src/mermaid-node.js`, `src/table-cell.js`) into a same-scope `const`. A module-private function called from the SDK closure compiles fine and only `ReferenceError`s on the first click, so put new helpers in one of those wholesale-serialized modules and export them; a helper may then reference only its own arguments, browser globals, or its sibling exports - never a module-level constant, which is not serialized. Those modules must export functions and nothing else: only functions survive `toString()`, so `serializeModuleHelpers` throws on any other export rather than shipping a `Set` or `RegExp` that would arrive as an empty `{}`. `test/artifact-sdk-bundle.test.js` boots the served bundle and drives a real click, which is what catches an unreachable helper; the module-level unit tests cannot.
+- Any helper `createArtifactSdk` calls must reach the browser as a same-scope `const` in `createSdkJs`. `src/artifact-sdk.js`'s own exports (everything except `createArtifactSdk` itself) are serialized automatically by iterating `Object.entries` of the module - a new exported helper needs no hand-kept entry in `src/server.js`. Helpers imported from the other shared modules (`src/mermaid-node.js`, `src/table-cell.js`) still go through `serializeModuleHelpers`, which turns every export of those modules into a same-scope `const`; a module-private function called from the SDK closure compiles fine and only `ReferenceError`s on the first click, so put new cross-module helpers in one of those wholesale-serialized modules and export them. Either way, a helper may reference only its own arguments, browser globals, or its sibling exports - never a module-level constant, which is not serialized. `serializeModuleHelpers` throws if `src/mermaid-node.js`/`src/table-cell.js` export anything but a function, since only functions survive `toString()`; the automatic `artifact-sdk.js` path additionally accepts non-function exports (JSON-stringified) for constants like `MODE_TOGGLE_HOTKEY_KEY`. `test/artifact-sdk-bundle.test.js` boots the served bundle and drives a real click, which is what catches an unreachable helper; the module-level unit tests cannot.
 - Table-cell annotations attach `src/table-cell.js`'s semantic row/column names as `target` only. The clicked element's own `selector`, `tag`, and `text` keep describing that element, because the on-screen highlight outlines exactly what was clicked. Both coordinates stay silent rather than name a row or column they cannot prove, because a confidently wrong name reads as authoritative and is worse than none: a rowspan is clipped to its own row group, so only one starting in an earlier row of that group (including `rowspan="0"`, which runs to the end of it) makes a row's DOM order stop being its rendered order, and that suppresses the row's positional heading - only a declared `scope="row"` heading survives it - while the column label needs the header row unshifted the same way, plus a row whose colspans sum to the header's and a cell that does not straddle a grouped header.
   A grouped header's `<th rowspan="2">` therefore costs the leaf header row its names and leaves every `<tbody>` row nameable.
   Spans come from the browser-parsed `rowSpan`/`colSpan` whenever present, because HTML's integer rules stop at the first non-digit and render `rowspan="2x"` as a real two-row span that `Number` reads as `NaN`. Resolving a cell walks its whole table, so `context()` computes the target only under `{ table: true }`, which the annotation card passes and `snapshot()` - which calls `context()` for every element in the document - deliberately does not.

README.md

@@ -197,6 +197,9 @@ pnpm link
   On wider screens, queued annotation preview pills and chat history share a scrollable Conversation panel above a sticky composer, so long feedback queues do not push the text box or send controls off screen.
   The browser chrome keeps editing actions in the overflow menu (copy path, reload artifact, copy DOM snapshot, export standalone HTML, publish link, end session), while the composer exposes **Send & End** beside **Send to Agent** to submit queued prompts and user-ended attribution together.
 - **Reviewing on a phone** - Below 860px wide, the artifact takes the whole screen above a **Conversation** dock, and the conversation opens as a bottom sheet over it: tap the dock, swipe it up, or press the chevron to raise it; tap the dimmed artifact, swipe the sheet down, press the chevron, or press Escape to lower it. The dock reports what matters while the sheet is down - how many prompts are queued, a reply that arrived while you were reading, or whether the agent is listening - and the sheet stays open across a reload of the review page. The sheet sizes itself to the visible viewport and respects safe-area insets; if the keyboard or attachments leave little room, conversation content yields or scrolls while the send actions remain pinned above the bottom edge. In landscape the sheet covers the top bar as well. Wider screens keep the side-by-side layout.
+- **Annotation indicators** - Every annotated element carries a small dot in the artifact, and sent annotations stay listed in the Conversation panel for the rest of the session, so it is always visible what has already been reviewed.
+  Navigation runs both ways: clicking a dot scrolls to and highlights its row in the panel, and clicking a panel row (a queued pill or a sent annotation) scrolls the element into view and flashes a marker around it.
+  The dots are only clickable in annotate mode, so they never intercept clicks meant for the artifact while exploring.
 - **Keyboard shortcuts** - In the chrome composer, Enter sends queued prompts and Shift+Enter inserts a newline.
   In the annotation card, Enter queues the annotation, Shift+Enter inserts a newline, and Ctrl+Enter (Cmd+Enter on macOS) queues it and sends all queued prompts immediately.
   Cmd+I or Ctrl+I toggles between annotate and explore mode from either the browser chrome or the artifact iframe, including while focus is in a textarea or control.