fix: helpful error messages when arguments are missing

[OfirHaim1]

Cobra's default arg-validation error is accepts 1 arg(s), received 0 — technically correct, tells the user nothing actionable, and forces a trip to --help.

Before / after on gitswitch add (no args)

Before:

$ gitswitch add
accepts 1 arg(s), received 0

After:

$ gitswitch add
gitswitch add requires an identity name

examples:
  gitswitch add work --email you@company.com
  gitswitch add personal              (interactive prompts for the rest)

run "gitswitch add --help" for the full reference.

The user gets: what's wrong, two worked examples to copy-paste, and the path to deeper docs — all without leaving the error.

Coverage

Command	Before	After
gitswitch add (0 args)	one-liner cobra error	usage + 2 examples
gitswitch delete (0 args)	one-liner cobra error	usage + 2 examples
gitswitch rename (≠2 args)	one-liner cobra error	usage + 2 examples
gitswitch use (0 or 3+ args)	one-liner cobra error	usage + 3 examples

Plus added Example: fields to every command (init, list, doctor, why, add, delete, rename, use) so --help itself surfaces a worked example block.

Implementation

internal/cmd/argshelp.go — small helper:

exactArgsHelp(n, usage, examples...) cobra.PositionalArgs
rangeArgsHelp(min, max, usage, examples...) cobra.PositionalArgs

Replaces cobra.ExactArgs(1) etc. at the call sites.

Release

fix: prefix → release-please will auto-bump to v1.1.1.

🤖 Generated with Claude Code
EOF
)