feat(webapp): dashboard agent — UI - #4529

Ask AI (Kapa) owns the two entry points it had before the dashboard agent
replaced it: Cmd-I, and the `?aiHelp=` deep link the CLI's "Get a fix for
this error using AI" line points at. `AskAIRoot` mounts in the `_app`
layout, above every signed-in page, so Cmd-I reaches it from org-level
pages too and the dialog outlives whatever opened it.

The agent no longer reads deep links at all: nothing produced its `?ask=`
param except the CLI redirect, and both readers consume the param, so a
live agent reader would always beat Kapa to it. It stays the fall-through
— where Kapa cannot open (self-hosted, or no website id), both channels
land on the agent instead of dead-ending.

…the pipeline emits

The fixture still set `facts.staleReason`, renamed to `untrustworthyReason` three commits
before the caveat started reading it, so the branch's only trust snapshot fell back to
"could not be verified" for a report whose reason is known.

The scheduled example lost its import line to the standard one, so copying
it gave code that does not compile.

Without org/project/env context the run button rendered but did nothing.

Shortcuts can now ask for the browser default to be prevented, and the
agent's keystroke does.

Selecting a stored chat with no messages dropped you into a fresh draft,
as if the chat had been deleted.

Radix tooltip content is not the accessible name of its trigger, so the
icon-only ask-agent button and the two deploy docs links announced as
unnamed controls. Name them explicitly and pass asChild so the tooltip
trigger stops wrapping them in a second button.

Adds a source scan that fails on the next SimpleTooltip with an unnamed
or double-wrapped control, with the pre-existing sites baselined.

A limit of 0 is zero capacity, not saturation: running >= 0 holds for every
queue, so any backlog marked the queue degraded and offered Investigate, while
the agent's own suggested prompt stayed silent. One predicate now decides it
for the queue detail page, the queues list badge and the page mappers.

Retry appended the last user message again, so the failed turn stayed in the
transcript and its text was sent twice. It now regenerates once the agent has
started answering, and otherwise re-sends the failed turn under its own id.

…e reader's clock

Bar timestamps came from Date.now() during render, so the same bar reported a
different time on every re-render and a server pass disagreed with the client.
They now come from the view model's generatedAt, which the schema already
describes as the timestamp the renderer must not invent.

Moves the arithmetic into report-spark.ts to keep it clock-free and testable,
and drops the unreachable Math.max on the slice end while doing so.

ViewBlocks looked each surviving block's index up with indexOf inside the render
loop: quadratic, and two occurrences of the same block object both answered with
the first index, so they collided on one React key. latestRevisionEntries carries
each survivor's position out instead.

setSearchParams only starts the navigation that drops the param, so a render
before it commits saw the question again and asked it a second time. The reader
now records what it sent and forgets it once the URL no longer carries it, so a
later visit with the same question still works.

A request still in flight at unmount rejected afterwards, and the catch scheduled
a retry that fetched again and set state for a component that was gone. The hook
tracks whether it is still mounted and neither records nor reschedules once it is
not.

The character counter's live region only entered the DOM at the warning point,
and several screen readers only announce updates for a region that was already
there; it is now always mounted and empty until there is something to say.

The history trigger's aria-label replaced the chat title it shows, so a
speech-input user could not activate it by the words on it. The title now leads
the accessible name.

…anel

justify-center on a scrolling column overflows equally in both directions, and
nothing can scroll back past the origin, so at the docked panel's narrowest the
heading and composer were unreachable. The child centres with m-auto, which gives
its space up once there is none to spare.

new URL(environmentPath, origin) ignores origin when the path is absolute, and
the result goes straight into redirect(). Today's only caller passes a
builder-generated internal path, so this closes the gap rather than a hole.

A preview branch named `env` put a second `env` segment in the path and
`lastIndexOf` picked it, shifting every index derived from it.

… keystroke

Between the warning point and the limit the region announced a new count
per character; it now steps in 200s and names the limit on reaching it.

… read

…review fixes

- `_app`: `AskAIRoot` is a sibling of the app, not a wrapper. Its Kapa provider
  mounts client-only, so wrapping the outlet remounted the whole signed-in tree
  once per page load on cloud. Entry points reach it through an open-request
  bridge instead of a render prop.
- The agent no longer hands a `trigger://source/...` target to `navigate`: a
  resolved GitHub URL opens in a new tab, and only a root-relative path is routed.
- Chat history reloads coalesce without answering a request with data fetched
  before it, so a new chat and its title land.
- Help & Feedback and the shortcuts sheet offer each AI surface only where the
  reader has it: Ask AI is back for users without agent access.
- Restore the `AskAgentButton` mount on the deploy blank states, dropped in the
  PR split.
- `agent-shortcuts.test.ts`: import ⌘I from `ask-ai-channels`.

…rface

Where neither Ask AI nor the agent can open, the redirect left `?aiHelp=` on the
environment page with nothing to read it. Send the question to the docs instead.