chore(deps): bump octocrab to 0.50 and refresh Cargo.lock

Run cargo update for in-range bumps (cc, idna_adapter, js-sys, libc,
pin-project, rustls, rustls-pki-types, tokio, wasm-bindgen, plus
octocrab 0.49.7 -> 0.49.9 within the previous 0.49 range), then bump
the Cargo.toml requirement octocrab 0.49 -> 0.50. octocrab 0.50 is a
SemVer-incompatible release but our usage (personal_token, base_uri,
.get/.post/.put/.patch/.delete typed and _-prefixed helpers) compiles
unchanged.

All 74 tests still pass and clippy stays warning-free against the new
versions.

The only crate cargo flags as still-behind is crypto-common
(0.1.6 -> 0.1.7), which is pinned through a transitive depgraph we
don't control.

Generated with [Claude Code](https://claude.ai/code)
via [Happy](https://happy.engineering)

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

Author: 3 people

Cargo.lock

@@ -20,7 +20,7 @@ path = "src/lib.rs"
 # Async runtime
 tokio = { version = "1", features = ["macros", "rt-multi-thread"] }
 # GitHub API client (de-facto standard for Rust)
-octocrab = "0.49"
+octocrab = "0.50"
 # JSON for parsing the event payload
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"