feat(modules): port lolschedule (5 commands; daily-push cron deferred)

Phase 6e (final sub-phase of port-plan Phase 06). LoL esports match
schedule via lolesports.com's persisted API.

- internal/modules/lolschedule:
  - api_client.go: HTTP client with cache-first lookup (120s fresh
    window, 60-min stale fallback). Cache record shape matches JS so
    cross-runtime KV migration round-trips.
  - parse_date.go: ICT-anchored date parser. Accepts dd-mm-yyyy,
    dd/mm/yyyy, ddmmyyyy; trailing month/year may be omitted (default
    to current ICT month/year). Rejects impossible dates (Apr 31, Feb
    29 in non-leap, etc.).
  - format.go: Today (grouped by league) and Week (grouped by league
    -> day) renderers. Major-league filter (LCK/LPL/LEC/LCS/Worlds/
    MSI/etc.) keeps replies under Telegram's 4096-char limit. All
    user-influenced strings HTML-escaped.
  - subscribers.go: Idempotent add/remove/list keyed by chat id.
  - handlers.go: 5 commands (`/lolschedule [date]`,
    `/lolschedule_today`, `/lolschedule_week`,
    `/lolschedule_subscribe`, `/lolschedule_unsubscribe`).
- 22 tests across api-client (cache hit / miss / stale fallback /
  hard fail / show filter / non-JSON), parse-date (full and
  short formats, defaults, rejections, ICT anchor), format (event
  line states, league ordering, week grouping, HTML escape, major
  filter), subscribers (idempotent add/remove), handlers (HTML
  reply, error path, subscribe/unsubscribe round-trip).

Daily-push cron deferred to Phase 09 (Cloud Scheduler). Subscribers
are still collected so the push lights up the moment the cron infra
lands. Deps doesn't currently expose a *bot.Bot reference; that is
the prerequisite that Phase 09 will solve.

go test -race -count=1 ./... clean (19 packages); golangci-lint clean.

cmd/server/main.go

@@ -18,6 +18,7 @@ import (
 	"github.com/tiennm99/miti99bot-go/internal/modules/loldleemoji"
 	"github.com/tiennm99/miti99bot-go/internal/modules/loldlequote"
 	"github.com/tiennm99/miti99bot-go/internal/modules/loldlesplash"
+	"github.com/tiennm99/miti99bot-go/internal/modules/lolschedule"
 	"github.com/tiennm99/miti99bot-go/internal/modules/misc"
 	"github.com/tiennm99/miti99bot-go/internal/modules/util"
 	"github.com/tiennm99/miti99bot-go/internal/modules/wordle"
@@ -39,6 +40,7 @@ func factories() map[string]modules.Factory {
 		"loldle-emoji":   loldleemoji.New,
 		"loldle-quote":   loldlequote.New,
 		"loldle-splash":  loldlesplash.New,
+		"lolschedule":    lolschedule.New,
 	}
 }