docs: document Go versions for rules

[ColumbusLabs]

Motivation

The available-rules table currently does not show which target Go versions each rule applies to. This makes version-gated rules difficult to identify without reading their implementations or individual descriptions.

Changes

• add a Go version column covering all 104 registered rules
• document minimum, maximum, and behavior-change versions from the rule implementations
• add the missing multiline-if-init table row so the table matches the rule registry
• explain Any and target-version semantics below the table

Closes #1311

[alexandear]

Thank you for the PR.

I have a few suggestions:

1. Please mirror the newly added Go version information to each rule in RULES_DESCRIPTIONS.md.
2. Use "1.0" instead of "Any". "Any" may be confused with the any alias for interface{}.
3. Document the behavior changes only in RULES_DESCRIPTIONS.md; this information is excessive for the table in README.md.