feat(#360): parameterized Dashboard Filter sources with single-layer dependencies

[BorisTyshkevich]

What & why

Closes #360.

Lets a Filter-role source query declare its own {name:Type} parameters and bind
committed root Dashboard filter values through the existing native
param_<name> pipeline (no textual SQL interpolation) — so a query-log option
source can compute its user / query-kind / exception-code lists for the selected
{from:DateTime} / {to:DateTime} window instead of a hard-coded range.
Single-layer only: a Filter source may depend on root filters, never on another
source-backed filter.

Builds directly on #359's one-FilterSourceRuntime-per-source boundary (merged).

Behavior

• A source waits (issues no ClickHouse request) until every required root
  parameter is committed, active, valid, and serializable — exposing a non-error
  waiting state that names the missing params.
• Relative values (-1d, now) resolve against one wall clock per wave.
• Native typed param_<name> args only — no textual interpolation.
• Changing a root filter reruns only the sources that declare it, then the
  affected panels, in one combined wave; a refreshed option set that drops a
  filter's active value deactivates it before panels run.
• A Filter source depending on another source-backed parameter is rejected
  with a visible filter-source-cascading diagnostic.
• A superseded source response can never publish stale results; a dependency
  change clears the affected options so a stale set can't appear current while
  the new source loads (no silent last-known-good).
• Dashboard execution and the Workbench Filter preview share one preparation
  op (prepareFilterSource) — identical structural diagnostics, relative-value
  resolution, optional-block materialization, validation/serialization, and args.
• Filter execution injects no readonly setting (kept from Refactor Dashboard Filter sources: execute once per source, preserve diagnostics, and reconcile option state #359).

Shape

• src/core/filter-execution.ts — new pure analyzeFilterSource +
  prepareFilterSource (the shared op) wrapping the existing param pipeline;
  the old filter-source-parameters diagnostic is removed. 100% covered.
• src/dashboard/application/dashboard-viewer-session.ts — FilterSourceRuntime
  gains analyzed/waiting; selective source rerun + combined panel wave;
  cross-source mid-flight guard; single preflight per commit; stale-options
  clear on the selective path. (Also removes a stray NUL byte from refactor(#359): one FilterSourceRuntime per unique Filter source query #361.)
• src/ui/{dashboard,filter-bar,filter-preview}.ts + styles.css — waiting /
  stale / error affordance for source-backed filters.
• src/application/workbench-parameter-session.ts + src/ui/workbench/workbench-session.ts
  — Workbench Filter preview uses the shared op via a prepareFilterPreview hook.
• examples/query-log-explorer.json — qle-filter migrated to a half-open
  {from:DateTime}/{to:DateTime} window (worked example).

Verification

• npm test green: 157 files / 4465 tests; per-file coverage gate holds (new
  core/UI/session code at/above threshold; filter-execution.ts 100/100/100/100).
• npm run build green (single dist/sql.html).
• e2e (chromium + webkit): existing Refactor Dashboard Filter sources: execute once per source, preserve diagnostics, and reconcile option state #359 cases + a new Allow Filter-role source queries to use root Dashboard parameters (single-layer dependencies) #360 case asserting
  waiting → runnable (one request, native param_from/param_to).
• Independent review passes (correctness/concurrency + parity/UI/layering) —
  found and fixed the double-preflight; verified the cross-source race guard,
  selective-rerun ordering, stale-options scoping, and stale-generation
  discipline hold.

Checklist

• npm test passes (the per-file coverage gate is non-negotiable)
• Tests added/updated in the same change as the code
• npm run build succeeds (single-file dist/sql.html)
• Layers kept honest: pure logic in src/core/, network in src/net/ (injected fetch), DOM in src/ui/
• No new runtime dependency
• README / CHANGELOG.md ([Unreleased]) updated (behavior changed)
• Reconciled affected tracked work (roadmap Roadmap to 1.0.0 #68, the issue body, CHANGELOG)

Review round (maintainer feedback on the merge-gate build)

Addressed all findings from the merge-gate review, as commits on this PR:

• Superseded/destroyed selective commit no longer runs its panel wave — a
  superseded source wave (per-source generation) or a destroy() now stops the
  affected-panel phase (findings 1+2). applyFilterProviders/runFilterSourceWave
  return applied | superseded; runAffectedWave got an unconditional destroyed
  guard. (A first attempt used a commit-level generation counter; a follow-up
  review showed it over-skipped legitimate unrelated overlapping commits, so it
  was removed — the per-source supersession check is sufficient and precise.)
• Param type-conflicts are errors, not runnable (finding 3) — analyzeFilterSource
  folds the pipeline's type-conflict diagnostics; a conflicted source errors on
  both surfaces, no request.
• Source-backed filters render by topology, not transient status (major UI) —
  curated renderer chosen by explicit sourceId; loading/stale/waiting applied
  imperatively (no rebuild, typing preserved), so the affordance shows on initial
  load and on a full refresh with existing options.
• Example consistency — qle-filter's {to} is now optional/inclusive,
  matching its panels.
• Dedup — runFilterWave/runFilterSourceWave share executeFilterSourcePlan;
  prepareFilterSource no longer re-runs structural diagnostics for transport params.

Re-verified: npm test (4482), npm run build, e2e chromium+webkit (154), plus a
second independent review pass.