Address PR TPC-Council#876 follow-up review: redo log capacity + dropdown trim

* src/mysql/mysqlci.tcl (mysql_init, mysql_start): replace the deprecated
  --innodb-log-file-size with --innodb-redo-log-capacity (supported from
  MySQL 8.0.30+). MySQL 5.7 is EOL so dropping that path is acceptable.
* modules/pipelines-1.0.tm: trim the database dropdown back to the three
  databases that actually run pipelines today (MySQL, PostgreSQL, MariaDB).
  Listing Oracle / SQL Server / Db2 there only ever produced the
  "not yet enabled" banner, so per review feedback they are commented out
  with a TODO note for re-enablement once build/install support lands. The
  dbprefix gate at lines 613 and 874 is left intact so direct ?db=ora|
  mssqls|db2 URLs still render the friendly banner.

Author: crprashant

modules/pipelines-1.0.tm

@@ -855,10 +855,16 @@ return
 
         wapp-subst {<div class="aut-form">}
 
-        # database chooser
+        # database chooser — only enabled databases are shown; commercial DBs
+        # (Oracle / SQL Server / Db2) will be added when build/install support
+        # lands (currently they would only show "not yet enabled").
         wapp-subst {<p><b>Database</b></p>}
         wapp-subst "<select class='aut-ctl' name='db' onchange=\"window.location='%html($B)/pipelines?db=' + encodeURIComponent(this.value)\">"
-        foreach {pfx label} [ list ora Oracle mssqls "SQL Server" db2 Db2 mysql MySQL pg PostgreSQL maria MariaDB ] {
+        # Future entries to add to the dropdown when supported:
+        #   ora    Oracle
+        #   mssqls "SQL Server"
+        #   db2    Db2
+        foreach {pfx label} [ list mysql MySQL pg PostgreSQL maria MariaDB ] {
             set sel ""
             if {$dbprefix eq $pfx} { set sel " selected" }
             wapp-subst "<option value='%html($pfx)'$sel>%html($label)</option>"

src/mysql/mysqlci.tcl

@@ -722,7 +722,7 @@ proc mysql_init {cidict refname} {
     if {$want_basedir} {
         lappend arglist "--basedir=\"$basedir\""
     }
-        lappend arglist "--innodb-log-file-size=[calc_redo_mb]M"
+        lappend arglist "--innodb-redo-log-capacity=[calc_redo_mb]M"
 
     # MySQL-specific: mysqld needs --initialize-insecure to perform first-time
     # data directory initialization (MariaDB uses scripts/mariadb-install-db
@@ -939,7 +939,7 @@ proc mysql_start {cidict refname} {
     if {$want_basedir} {
         lappend arglist "--basedir=\"$basedir\""
     }
-        lappend arglist "--innodb-log-file-size=[calc_redo_mb]M"
+        lappend arglist "--innodb-redo-log-capacity=[calc_redo_mb]M"
     # Note: --thread-pool-size is intentionally omitted here. The thread_pool
     # plugin is only bundled with MySQL Enterprise Edition; Community builds
     # (what cipush compiles from source) abort startup with "Plugin 'thread_pool'