refactor(server): dedupe shard-state shaping, upsert builder, and config DB models

Address the SonarQube copy-paste findings that reflect real duplication (as
opposed to the intentional cross-package / admin-player mirror copies, which
are by-design and left as-is):

- shardState.model.js: listOnline() re-inlined the exact field mapping that
  shapeOnline() already provides (used by listOnlineLinked). Collapse it onto
  shapeOnline so the two can no longer drift.
- shardState.db.js: extract a single upsertRow(table, pkCol, pk, fields,
  {coalesce}) builder for the five near-identical INSERT ... ON DUPLICATE KEY
  UPDATE bodies (online/houses/champs/guilds/governors). shard_online keeps its
  COALESCE-on-NULL semantics via the coalesce flag.
- botConfig/emailConfig/uoLinkConfig .db.js: generate get()/upsert() from a
  shared singletonConfigDb(table, cols) factory instead of three byte-identical
  copies.

Behavior unchanged; full server suite (381 tests) passes.

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

server/src/model/botConfig/botConfig.db.js

@@ -1,28 +1,7 @@
-const { query } = require('../../utils/db')
+const singletonConfigDb = require('../singletonConfigDb')
 
 const COLS =
   'id, guild_id, bot_token_enc, application_id, enabled, status, status_detail, last_connected_at, updated_by, created_at, updated_at'
 
-// Singleton row (id = 1). Returns null until the admin saves it for the first time.
-async function get() {
-  const rows = await query(`SELECT ${COLS} FROM bot_config WHERE id = 1 LIMIT 1`)
-  return rows[0] || null
-}
-
-// Upsert the singleton row. `fields` are column values already prepared by the
-// model (token pre-encrypted). Only the provided columns are written/updated.
-async function upsert(fields) {
-  const cols = Object.keys(fields)
-  const vals = cols.map((c) => fields[c])
-  const insertCols = ['id', ...cols].map((c) => `\`${c}\``).join(', ')
-  const placeholders = ['1', ...cols.map(() => '?')].join(', ')
-  const updates = cols.map((c) => `\`${c}\` = VALUES(\`${c}\`)`).join(', ')
-  await query(
-    `INSERT INTO bot_config (${insertCols}) VALUES (${placeholders})
-     ON DUPLICATE KEY UPDATE ${updates}`,
-    vals,
-  )
-  return get()
-}
-
-module.exports = { get, upsert }
+// Singleton row (id = 1). See ../singletonConfigDb for the get/upsert contract.
+module.exports = singletonConfigDb('bot_config', COLS)