docs(telemetry): add decision tree, MCP guidance, and cross-links (MED)

- telemetry.mdx: adds "Start here" decision tree, docs-first architecture note
  in the AI agents section, and expanded chaos-o11y mention
- debugging.mdx: adds MCP tip admonition at the top; adds "For AI agents"
  section at the bottom describing the get_logs-first workflow
- logs.mdx: adds debugging guide back-link at the top; adds advanced-log-
  filtering cross-link at the end of best practices

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/docs/content/guides/monitoring-and-debugging/logs.mdx

@@ -358,6 +358,9 @@ Identify which service owns the problem from the error or status code first, the
 
 A misspelled or non-existent field name either errors or silently returns nothing, which leaves a working query look empty. Confirm field names in the [field reference](#logs-field-reference), or select `event_message` and inspect a sample row first.
 
+For regular expression filtering, structured-field queries, and field discovery techniques, see [Advanced log filtering](/docs/guides/telemetry/advanced-log-filtering).
+
+
 ### Logs field reference
 
 Refer to the full field reference for each source below. Each source's structured fields are listed as ClickHouse `log_attributes` keys, alongside the base columns (`id`, `timestamp`, `event_message`, `severity_text`, `source`) that every source has.