docs(examples): add resumable Calls V2 examples

[JJasonSun]

Summary

Add complete Python SDK and Ruby HTTP Calls V2 examples that save the original request and key before submission, save the resource ID before waiting, and resume the same operation after a timeout or lost response.

start  -> save request/key -> create -> save ID -> wait for result_status
resume -> read saved ID (or replay saved request/key) -> wait -> save result
reader -> preserve result, error, call_outcome, result_status and transcript

Point quickstart, authentication, Calls and SDK guidance to these examples and pin published SDK 1.0.1. Existing legacy examples remain available under their original filenames for historical call-task IDs.

API contract

Not changed. The examples follow the existing public /v2/calls OpenAPI contract.

Evidence

• Before: Current guides referenced legacy runnable files or SDK 1.0.0, which is not the published release.
  After: Python and Ruby start/resume flows completed real official-hotline calls with SDK 1.0.1 / HTTP V2, preserved the original request and ID, and saved schema-valid available results and transcripts. The local reader preserved the real response fields. Ruby recovered a temporary create rejection using its unchanged saved request and key.
• Supplemental Python and Ruby checks cover lost create responses, unchanged replay, known-ID read-only resume, completed execution with pending results, and final unavailable/empty results.
• pnpm run validate passed, including build, deployment checks and 32 Playwright tests. Example checks and git diff --check passed.

Checklist

• I kept the change focused and public-facing.
• I removed secrets, private URLs, phone numbers, and customer data.
• Any OpenAPI change describes behavior supported by the public API. (No OpenAPI change.)
• I updated tests when observable site behavior changed.
• I added screenshots for visual changes. (No visual design change.)
• I ran pnpm run validate.

Merge Danger

Door: two-way

Revert the new files and links to roll back. No schema or stored-data migration is performed.

Blast Radius: examples

Each intentionally new start can place a real call; resume preserves the saved operation. No merge or production publication is included.