No need to set `HYPERCRUSH=1` anymore.

The model was enable to edit `internal/ui/model/ui.go` for me, because
it has ~ 108KB and the limit was 100KB.
(Without being able to read, the model also can't update it).

We're keeping the `fetch` tool limit to 100KB.

Fixes the SSE multi-consumer bug where multiple clients sharing the same
workspace received only a fraction of events (competing-consumer semantics
on a plain channel). Each caller to Events()/SubscribeEvents() now gets
its own dedicated channel via Broker.Subscribe(ctx).

💘 Generated with Crush

Assisted-by: AWS Claude Sonnet 4.6 via Crush <crush@charm.land>

The runner now compiles its own matchers, so a config round-trip can't
silently strip them. Hooks with an invalid matcher are dropped with a
warning instead of quietly matching everything.

A hook with a matcher like "^bash$" was firing on every tool call
after any config write, because the compiled regex was dropped when
the config reloaded. Recompile on reload so filtering keeps working.

Prior to this fix, notifications in the footer would not span the width
of the window, and text truncation would often happen prematurely.