docs: audit and fix docs/english markdown files

[lukegalbraithrussell]

Summary

Audited all docs/english/ markdown files against source code for accuracy, fixed inaccuracies, corrected spelling/grammar, and migrated heading ID syntax for Docusaurus 3.10 compatibility.

Category	Description
Docusaurus 3.10 migration	Converted all 114 {#id} heading anchors to {/* #id */} JSX comment syntax
Incorrect class/method references	Fixed AsyncWebhookClient → AsyncWebClient, prepare_for_next_retry → prepare_for_next_attempt, slack_sdk.http_retry RetryHandler → slack_sdk.http_retry.RetryHandler
Copy-paste errors	Fixed audit-logs.md referencing "SCIM API" / "AsyncSCIMClient" instead of Audit Logs equivalents
Incorrect module paths	Fixed slack.rtm_v2.RTMClient → slack_sdk.rtm_v2.RTMClient in rtm.md
Wrong variable names	Fixed client.retry_handlers → webhook.retry_handlers in webhook.md
Incorrect API references	Fixed filter param value in scim.md (removed redundant filter= prefix)
Broken URL	Fixed https://tools slack.dev/... → https://docs.slack.dev/tools/... in v3-migration.md
Code example inconsistency	Fixed mismatched callback_id and removed duplicate paragraph in web.md
Undefined variables	Fixed client_id / redirect_uri references in oauth.md callback example
Spelling and grammar	Fixed typos ("pockage", "Adaptor", "straight-forward"), grammar ("supports" as noun, subject-verb agreement, missing articles/prepositions, "its" vs "it's"), and word errors ("methods in those methods" → "modules")

🤖 Generated with Claude Code

Co-Authored-By: Claude svc-devxp-claude@slack-corp.com

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 84.11%. Comparing base (2491a2d) to head (8ef0b13).
⚠️ Report is 1 commits behind head on main.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@ Coverage Diff @@## main #1883 +/- ##
==========================================
- Coverage 84.14% 84.11% -0.03% 
==========================================
Files 117 117 Lines 13356 13356 ==========================================
- Hits 11238 11234 -4 - Misses 2118 2122 +4 

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