Add the crawl job API and Tor diagnostics

[KingAkeem]

What changed

• adds a versioned JSON crawl report and cancellable REST job API
• restores health/readiness endpoints and adds Tor configuration diagnostics
• returns parent relationships, metadata, contacts, skip reasons, and partial errors
• adds per-host limits, content guardrails, randomized user agents, and structured logging
• hardens the container and CI workflow
• refreshes the README, API reference, and changelog

Why

TorBot App previously had no stable backend integration surface. The concurrent crawler also removed the older REST service and only logged results, which made it difficult for desktop and automation clients to consume crawl state safely.

Impact

Clients can now start, poll, and cancel jobs through /api/v1/jobs. They can also inspect SOCKS reachability and local torrc details through /api/v1/tor/status. CLI users retain list/tree output and gain a stable -f json format.

Validation

• go vet ./...
• go test -race -cover ./...
• go build -trimpath ./cmd/main
• live direct crawl of https://example.com
• Electron adapter end-to-end job and Tor-status smoke test

Related issues

Closes #44
Closes #72
Closes #74
Closes #76
Addresses part of #77