drivers: Migrate camelCase public methods to snake_case.

[nedseb]

Problem

Several drivers used camelCase for public methods, while the project convention is snake_case.

Resolution

All camelCase public methods have been migrated to snake_case across 4 drivers, and ruff rules have been enabled to prevent regressions.

Sub-issues (all completed)

Per-driver migration

• hts221: Migrate camelCase methods to snake_case. #131 — hts221: 7 methods renamed (PR hts221: Migrate camelCase methods to snake_case. #136)
• vl53l1x: Migrate camelCase I2C helpers to snake_case. #132 — vl53l1x: already compliant, comments cleaned (PR vl53l1x: Remove camelCase references from configuration comments. #137)
• bq27441: Migrate camelCase methods to snake_case. #133 — bq27441: 28 methods + local variables renamed (PR bq27441: Migrate camelCase methods to snake_case. #138)
• apds9960: Migrate camelCase methods to snake_case. #134 — apds9960: 66 methods renamed (PR apds9960: Migrate camelCase methods to snake_case. #139)

CI enforcement

• ci: Add ruff rule to enforce snake_case method naming. #135 — ruff N802, N803, N806, T20 rules enabled (PR ci: Enable ruff rules to enforce snake_case method naming. #140)

Final state

Driver	Status
apds9960	snake_case (66 methods migrated)
bq27441	snake_case (28 methods migrated)
hts221	snake_case (7 methods migrated)
ism330dl	snake_case (always was)
lis2mdl	snake_case (variables cleaned)
mcp23009e	snake_case (always was)
ssd1327	snake_case (example fixed)
vl53l1x	snake_case (comments cleaned)
wsen-hids	snake_case (variables cleaned)
wsen-pads	snake_case (always was)

Ruff rules enabled

• N802: function name should be lowercase
• N803: argument name should be lowercase
• N806: variable in function should be lowercase (examples excluded)
• T20: no print() in production code (examples and tests excluded)

No backward-compatibility aliases were added (no release has been made yet).

Next steps

This issue unblocks the remaining harmonization issues (#76–#81).