docs(cli): remove non-existent commands (upgrade, config, --flavor)

[galligan]

Summary

Documentation references CLI commands and options that don't exist in the implementation.

Findings

Issue ID	Description
CLI-001	--flavor option documented in docs/cli/commands.md but not implemented
CLI-002	upgrade command documented in docs/cli/commands.md and docs/cli/howto.md but doesn't exist
CLI-003	config command removed in v1.0.0-beta.1 but still documented

Files to Update

• docs/cli/commands.md - Remove references to upgrade, config, --flavor
• docs/cli/howto.md - Remove blz upgrade examples

Source of Truth

• crates/blz-cli/src/cli.rs - Actual CLI implementation

Priority

Critical - These commands will fail if users try them.

[linear]

BLZ-311