fix(eventbus): add missing type declarations for EventBus subpath exports

[YevheniiKotyrlo]

Defect Fixes

Fixes #8422

The four EventBus subpath exports (primevue/toasteventbus, primevue/overlayeventbus, primevue/confirmationeventbus, primevue/dynamicdialogeventbus) ship JavaScript but no .d.ts type declarations. Projects using skipLibCheck: false get TS7016 errors — every other PrimeVue subpath export (100+ modules) includes type declarations except these four.

Problem

import ToastEventBus from 'primevue/toasteventbus';
// TS7016: Could not find a declaration file for module 'primevue/toasteventbus'

ToastEventBus.on('add', (message) => {
  // message: any — no type safety for event payloads
});

After this fix, all event bus operations are fully typed:

import ToastEventBus from 'primevue/toasteventbus';

ToastEventBus.on('add', (message) => {
  // message: ToastMessageOptions — full autocomplete and type checking
  console.log(message.severity, message.summary);
});

Root cause

The source directories for these four modules only contain .js and package.json files — no .d.ts — so the build pipeline (copyDependencies in postbuild.mjs) has nothing to copy to dist/.

Changes

• Add index.d.ts for each EventBus module with typed overloads for on, off, emit, and clear
• Add "types": "./index.d.ts" to each module's package.json
• Event types reuse existing PrimeVue types (ToastMessageOptions, ConfirmationOptions, DynamicDialogInstance)
• Follows the inline typing pattern used by TerminalService.d.ts

Scope / Impact

• No breaking changes — adds missing declarations, previously resolved as any
• No runtime changes — types only (.d.ts + package.json types field)
• 4 modules: toasteventbus, overlayeventbus, confirmationeventbus, dynamicdialogeventbus

Verification

Gate	Result
tsc --noEmit with skipLibCheck: false	TS7016 resolved for all 4 modules
Event types match runtime behavior	Verified against source
All CI gates (format, lint, test, build)	PASS