fix: apply all audit findings (timeouts, rate-limit capture, pagination, UI gaps, auth gating) - #6

Capture ran after map_status, so 401/403/404 responses never updated
the rate-limit state and the dashboard freshness stamp. Capture now
runs first, keeping the badge and last-updated timestamp honest even
when requests start failing.

'Load more' previously called gloo_net directly in the app crate,
bypassing the rate-limit capture, error classification, and the new
request timeout. Adds GithubClient::get_page and funnels the raw
Link-header cursor through it (AGENTS.md §3.2).

…ounds

The pagination-derived count multiplied per_page by the rel=last page
count, silently including pull requests (GitHub mixes them into the
issues endpoint) and presenting the upper bound as an exact number.
Page 1 is now counted exactly (PRs filtered), later pages are assumed
full, and results render as N+ with a tooltip when estimated.

Also: the card view now uses the same totals, estimate markers, and
shows the last-push label that the table view already had.

…nses

The interval effect subscribed to the rate-limit signal, so any fetch
anywhere in the app (e.g. the repo detail page) re-ran the effect and
restarted the countdown. The effect now tracks only the interval setting;
the tick closure reads token and rate limit untracked and simply no-ops
while the limit is nearly exhausted.

Rapidly changing filters could start two fetches whose responses
arrived out of order, with the older response overwriting the newer
list (last-write-wins). Each fetch now captures a generation counter
and only applies its writes while it is still the latest request.

…ilures

Repo detail now tracks per-tab error signals: a failed first load shows
an error panel (not a misleading "No issues"), and a failed load-more
keeps the list and shows the reason under the button. The dashboard
counts repos whose entire bundle failed and shows a banner pointing at
the token or rate limit. Loading state moved into the fetch functions
so load-more clicks set it reliably.

…keletons

Three small CSS/class fixes from the audit:

- --typography-button-sm and --typography-body-sm were referenced by
  .label, .rl-badge-wrap, .view-toggle button and .repo-table but never
  defined, so those declarations were dropped by the browser. Both
  tokens now exist (matching DESIGN.md's typography table).
- The login page used class "page--login" while the stylesheet defined
  ".page-login", so its max-width/centering never applied. The class
  now matches.
- Skeleton rows lost their fixed widths when the inline style
  attributes were removed; width classes were added for them.

…PR rows

AGENTS.md §5.3 specifies each row shows the author avatar and the
last-updated date; the rows only had the plain author name, comment
count and labels. Rows now render a 20px avatar (when the API provides
one) and a YYYY-MM-DD date parsed from updated_at.

…ction

The refresh-interval select only handled change events; after a reload
it always showed "Manual only" because no value was bound to the
current RefreshInterval. The select now uses prop:value via a new
RefreshInterval::value() helper. The theme section (AGENTS.md §5.6)
was missing entirely: two Light/Dark buttons that persist through
SettingsState::save_theme.

auth.logout() called storage::clear_all(), wiping the watchlist and
refresh/theme preferences together with the token — losing the user's
setup on every logout. It now deletes only the token key. The doc
comment claiming logout resets the rate-limit state (which is done by
the caller) is corrected.

…shboard

Only "/" showed the login page when logged out; /repo/:owner/:repo and
/settings rendered their UI with no token, which then failed silently
or looked broken. A small AuthedView wrapper (ChildrenFn + dynamic
closure, since Leptos 0.8's Show requires Fn children) now guards all
three routes and redirects the view to LoginPage until the token is
validated. Also removed the now-unused storage::clear_all and an unused
variable.

The endpoints built their request URLs inline with format!, leaving
URL composition untested and the ROADMAP's "mock the API layer" claim
half-true. URL building is now extracted into small pure functions
(user_url, repo_url, issues_url, pulls_url, workflow_runs_url) used by
both the live request path and new unit tests covering default and
full parameter sets. 8 new tests, still zero network access.

Three claims no longer matched the source:

- Section 3 (own look) marked everything done, but 294d214 reverted
  the dark-first/sky-blue rework back to the warm-cream, light-first
  palette with Pinterest Red as the sole accent. Items are unchecked
  again with reverted notes; the tokenization and favicon items stay
  checked since they survived.
- Section 2 claimed a hand-rolled mock of the GithubApi trait. What
  actually exists is pure URL-builder functions with unit tests, so the
  item is reworded to match and the acceptance text updated.
- The test count is updated to the current 48 (37 github-api + 11
  models) and the "borrowed visual identity" summary reflects the
  revert.

The settings page duplicated the theme switcher that already lives in
the navbar; theme is now changed only from the header toggle.

The shimmer skeletons in the dashboard fallback and the issue/PR tab
lists were rough and noisy. Loading states now render a muted
"Loading…" text (dashboard) / "Loading issues…" / "Loading pull
requests…" line. All skeleton CSS was removed; the button spinner used
by load-more and the token form is unchanged.

The selects and inputs in the detail toolbar had no gap between them,
so the state/sort/label/author controls sat flush against each other.
.filters is now a flex row with a gap, wrapping on narrow widths.