chore(release): 2.3.0 [skip ci]

chore: replace .commitlintrc.json with commitlint.config.cjs and update .dockerignore

refactor(tests): use username in mocks and adjust nickname validation

chore: update Node.js version requirement to >= 20.19.0 and update biome schema version to 2.4.6

docs: add .kiro/specs/env-standardization/design.md

chore: add .kiro/specs/env-standardization/.config.kiro

docs: add docs/ENV_VARS.md

docs: add docs/BRIDGE_INTEGRATION.md

docs(agents): add apps/portal/tests/AGENTS.md

feat(integrations): add apps/portal/src/features/integrations/lib/bridge/keys.ts

chore(db): add packages/db/drizzle/20260314151330_nosy_victor_mancha/snapshot.json

chore(db): add packages/db/drizzle/20260314151330_nosy_victor_mancha/migration.sql

chore(types): update packages/types/src/api.ts

chore(schemas): update packages/schemas/src/user.ts

chore(schemas): update packages/schemas/src/integrations/xmpp.ts