enhance: inherit team access for all units (#38938)

Admin and write team authorize now grant that mode on every unit,
including units added later, instead of only rows present in
`team_unit`. Granular teams keep `authorize=none` and explicit unit
rows.

Closes the `TEAM-UNIT-PERMISSION` design gap from
https://github.com/go-gitea/gitea/pull/34128.

Maybe also fix #15962 (actually maybe it had been fixed before, the root
cause is out-of-sync "access" table)


## Screenshots

only writing selected:
<img width="1399" height="1007" alt="image"
src="https://github.com/user-attachments/assets/1d1b4c49-a59a-47b6-998f-0464a067395b"
/>


_Created with the help of AI_

---------

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

options/locale/locale_en-US.json

@@ -2845,8 +2845,9 @@
   "org.teams.read_access_helper": "Members can view and clone team repositories.",
   "org.teams.write_access": "Write",
   "org.teams.write_access_helper": "Members can read and push to team repositories.",
+  "org.teams.write_access_all_helper": "Members get write access for all units to the team repositories.",
   "org.teams.admin_access": "Administrator Access",
-  "org.teams.admin_access_helper": "Members can pull and push to team repositories and add collaborators to them.",
+  "org.teams.admin_access_helper": "Members get administrator access to the team repositories.",
   "org.teams.no_desc": "This team has no description",
   "org.teams.settings": "Settings",
   "org.teams.owners_permission_desc": "Owners have full access to <strong>all repositories</strong> and have <strong>administrator access</strong> to the organization.",