docs(plugin-chassis): address PR-#5690 review feedback

CodeRabbit + Gemini review pass surfaced four small doc-precision
items, all legitimate. None were code bugs.

# CodeRabbit (markdownlint nit)

- doc/PLUGIN_API.md:455: fenced code block at "DISK ↔ MEMORY ↔
  RUNTIME" lacked a language specifier. Added `text` to satisfy
  MD040 / fenced-code-language.

# Gemini (3x same root: clarify the matching algorithm)

The chassis dispatch matcher is case-insensitive whole-identifier
substring match, but three docs described it loosely. Plugin
authors deciding what table name to register need to know that
runtime_X does not match runtime_X_extra or stats_runtime_X.

- doc/PLUGIN_API.md:289 ("any admin SELECT against it") -> spell
  out the whole-identifier rule with the longer-prefix /
  longer-suffix rejection examples.
- doc/plugin-chassis/ABI.md:156 ("appears in the SQL") -> "is
  referenced as a whole identifier in the SQL query
  (case-insensitive; identifier-aware, so runtime_X_extra or
  stats_runtime_X do not match runtime_X)".
- doc/plugin-chassis/FILE_CHANGES.md:102 ("substring match") ->
  "case-insensitive whole-identifier substring match", matching
  the precise wording already used in section B for the
  sql_references_table_ci helper. Cross-section consistency.

No source code touched. No new content sections, only existing
prose tightened.

doc/PLUGIN_API.md

@@ -286,9 +286,13 @@ bool register_runtime_view(const ProxySQL_PluginRuntimeView &view);
 Declare an admin-side **view** of plugin-module state. The named
 `table_name` lives in `admin_db` (typically `runtime_<something>`) and
 holds no persistent rows — the chassis invokes `refresh(admindb,
-opaque)` before any admin SELECT against it. The refresh callback is
-expected to do (typically) `BEGIN; DELETE FROM <table>; INSERT/REPLACE
-INTO <table> ...; COMMIT;` from the module's own in-memory state.
+opaque)` before any admin `SELECT` that references the table as a
+whole identifier. The match is case-insensitive but identifier-aware:
+a query against `runtime_<table>_extra` (longer suffix) or
+`stats_runtime_<table>` (longer prefix) does NOT trigger the refresh
+for `runtime_<table>`. The refresh callback is expected to do
+(typically) `BEGIN; DELETE FROM <table>; INSERT/REPLACE INTO
+<table> ...; COMMIT;` from the module's own in-memory state.
 
 The chassis deep-copies `table_name` so the plugin need not keep the
 pointed-to string alive after registration. The callback pointer must
@@ -447,7 +451,7 @@ callbacks, not by linking against ProxySQL's SQLite wrapper.
 
 ProxySQL's three-tier configuration model is, in storage terms:
 
-```
+```text
 DISK (config_db)  ↔  MEMORY (admin_db editable tables)  ↔  RUNTIME (in-module state)
 ```
 

doc/plugin-chassis/ABI.md

@@ -153,7 +153,7 @@ Therefore:
 
 - `LOAD <X> TO RUNTIME` reads the editable admin table and hands the rows to the module via a typed install API that swaps state under the module's own lock. It MUST NOT touch `runtime_<X>`.
 - `SAVE <X> [FROM RUNTIME] TO MEMORY` dumps the module's in-memory state and `REPLACE INTO`s the editable admin table. It MUST NOT read `runtime_<X>`.
-- `runtime_<X>` is repopulated by the registered refresh callback before any admin SELECT touches it. Admin's pre-SELECT hook walks every registered view and invokes the callback for any whose table name appears in the SQL.
+- `runtime_<X>` is repopulated by the registered refresh callback before any admin SELECT touches it. Admin's pre-SELECT hook walks every registered view and invokes the callback for any view whose table name is referenced as a whole identifier in the SQL query (case-insensitive; identifier-aware, so `runtime_<X>_extra` or `stats_runtime_<X>` do not match `runtime_<X>`).
 
 Disk-tier copies (`LOAD <X> FROM DISK`, `SAVE <X> TO DISK`) are the exception: those DO copy between configdb and admindb persistent tables, and they remain plain `BEGIN/DELETE/INSERT/COMMIT` with checked rollback. For those, the **empty-source-must-still-clear-destination** rule still applies — a `DELETE FROM mysqlx_users; SAVE MYSQLX USERS TO DISK;` must leave the disk table empty, not preserve the previous rows. PR #5643 fixed an early mysqlx implementation that omitted the unconditional DELETE on the disk path.
 

doc/plugin-chassis/FILE_CHANGES.md

@@ -99,7 +99,7 @@ Sections **A–G** cover the **chassis core**. Sections **H–O** cover the **my
   - Three free functions `proxysql_plugin_get_admindb/configdb/statsdb()` return `GloAdmin->{admindb,configdb,statsdb}` if `GloAdmin` is non-null. Gated by `PROXYSQL40` so v3.x exports no plugin-aware symbols at all.
   - `ProxySQL_Admin::dispatch_plugin_admin_command<S>(sess, sql)` builds a `ProxySQL_PluginCommandContext{admindb,configdb,statsdb}`, calls `proxysql_dispatch_configured_plugin_admin_command`, and translates `result` into `send_ok_msg_to_client` / `send_error_msg_to_client`.
   - Explicit template instantiations for `MySQL_Session` and `PgSQL_Session`.
-  - **Pre-SELECT runtime-view dispatch in `GenericRefreshStatistics`** (around line 1654): `proxysql_refresh_configured_plugin_runtime_views(query_no_space, admindb)` is called for **every admin-port query**, gated only on `if (admin)` and placed **outside** the existing `if (refresh==true)` block. The chassis itself decides whether any plugin's refresh callback fires, by per-view substring match against the query — a query that touches no registered view is a cheap no-op (one shared lock + N substring scans). The `refresh` flag is left untouched; it gates a separate set of core-only refreshes (stats_mysql_processlist, runtime_mysql_users, etc.).
+  - **Pre-SELECT runtime-view dispatch in `GenericRefreshStatistics`** (around line 1654): `proxysql_refresh_configured_plugin_runtime_views(query_no_space, admindb)` is called for **every admin-port query**, gated only on `if (admin)` and placed **outside** the existing `if (refresh==true)` block. The chassis itself decides whether any plugin's refresh callback fires, by case-insensitive whole-identifier substring match against the query (matching the wording used in section B for the `sql_references_table_ci` matcher) — a query that touches no registered view is a cheap no-op (one shared lock + N substring scans). The `refresh` flag is left untouched; it gates a separate set of core-only refreshes (stats_mysql_processlist, runtime_mysql_users, etc.).
 
 ### `include/proxysql_admin.h` — MODIFIED, +8 lines