cli: --help examples reference old binary name `mcp-cli` instead of `mcp-execution-cli`

[bug-ops]

Description

PR #90 removed the hardcoded `#[command(name = "mcp-cli")]` attribute from `Cli` so that clap derives the binary name from argv[0] at runtime. This correctly fixed `--version` output and shell completions. However, the inline code examples embedded in doc comments in `crates/mcp-cli/src/cli.rs` were not updated and still reference the old name `mcp-cli`. These examples appear verbatim in `--help` output, creating an inconsistency between the `Usage:` line (correct) and the examples (wrong).

Reproduction Steps

1. Run `mcp-execution-cli introspect --help`
2. Observe: `Usage: mcp-execution-cli introspect [OPTIONS] [SERVER]` — correct
3. Observe in the long description: `mcp-cli introspect --from-config github` — wrong binary name
4. Same issue in `mcp-execution-cli generate --help` and `mcp-execution-cli skill --help`

Expected Behavior

All examples in `--help` output reference the correct binary name `mcp-execution-cli`.

Actual Behavior

`--help` examples show `mcp-cli` while `Usage:` correctly shows `mcp-execution-cli`. This confuses users copying examples from help text.

Affected Files

`crates/mcp-cli/src/cli.rs` — lines 46, 51, 58, 61, 64, 67, 70, 75, 150, 153, 156, 161, 209, 214, 224, 227

Environment

• Version: 0.7.0 (HEAD c7c5e1b)
• CI-004 live testing session

Logs / Evidence

```
$ mcp-execution-cli introspect --help
...

1. Load from ~/.claude/mcp.json (recommended): ```bash mcp-cli introspect --from-config github ```
   ...
   Usage: mcp-execution-cli introspect [OPTIONS] [SERVER]
   ```