Update documentation to enhance clarity on native language and skill generation

- Revised `AGENTS.md` to specify that the same seed, map, name set, and native language must produce the same roster in tests.
- Updated `protocol.md` to clarify that everyone in the school is generated with the selected native language, and related languages may appear at a low skill.
- Enhanced `ai.md` to explain skill growth mechanics based on state and the introduction of minimum ranges for skills not yet acquired.
- Improved `people.md` to detail the generation of skills and traits, emphasizing that not every person receives every skill and the implications of body attributes on skill acquisition.
- Adjusted `projects.md` to reflect the inclusion of native language in roster generation, ensuring comprehensive documentation of project components.

AGENTS.md

@@ -108,8 +108,8 @@ say so explicitly in the change description.
 
 - Simulation changes need a `GameClock` or `SchoolRegistry` test. They are fast and need no host.
   Putting a roster into `World` and ticking needs belongs there too.
-- People generation belongs in `tests/HSchool.People.Tests`. Same seed, map and name set must
-  produce the same roster; the suite does not boot a host.
+- People generation belongs in `tests/HSchool.People.Tests`. Same seed, map, name set and
+  native language must produce the same roster; the suite does not boot a host.
 - Timetable planning belongs in `tests/HSchool.Schedule.Tests`. Same staff, map and locks must
   produce the same table; the suite does not boot a host.
 - Walking and day plans belong in `tests/HSchool.Ai.Tests`. Same seed and map must produce the