[Docs] Remove obsolete Nereids replay documentation - #4143

Summary

• Remove the PLAN REPLAYER DUMP page and sidebar entry from the dev English and Chinese docs.
• Remove the obsolete nereids_trace_log_dir FE configuration documentation.
• Keep versioned documentation unchanged because [refactor](nereids) Remove minidump, plan replayer, and tracing doris#67811 targets master; the older versions still retain these interfaces.

Related code change: apache/doris#67811

No redirect is added because the removed statement and endpoint have no replacement. Versioned documentation URLs remain available for older releases.

Validation

• git diff --check
• Changed-file link lint (only the expected deleted-page redirect-review warnings)
• Changed-file i18n sync lint (only the expected dev/versioned-doc exception warnings)

Versions

• dev
• 4.x
• 3.x
• 2.1 or older (not covered by version/language sync gate)

Languages

• Chinese
• English

Docs Checklist

• Checked by AI
• Test Cases Built
• Updated required version and language counterparts, or explained why not
• If only one language changed, confirmed whether source/translation counterparts need sync (N/A: both languages changed)