Move robot base classes from opmode to framework

[PeterJohnson]

Having these in opmode will be confusing to users when opmodes are added.

[github-actions]

This PR modifies commands. Please open a corresponding PR in Python Commands and include a link to this PR.

[KangarooKoala]

Seems alright to me, for what it's worth. grep and find say this got all of the instances of opmode:

% git fetch upstream pull/8344/head && git checkout --detach FETCH_HEAD && grep -r 'opmode' . && find . -path '*opmode*'
From https://github.com/wpilibsuite/allwpilib
 * branch                  refs/pull/8344/head -> FETCH_HEAD
HEAD is now at 3566b71202 Move robot base classes from opmode to framework

[KangarooKoala]

Seems alright to me, for what it's worth. grep and find say this got all of the instances of opmode:

% git fetch upstream pull/8344/head && git checkout --detach FETCH_HEAD && grep -r 'opmode' . && find . -path '*opmode*'
From https://github.com/wpilibsuite/allwpilib
 * branch                  refs/pull/8344/head -> FETCH_HEAD
HEAD is now at 3566b71202 Move robot base classes from opmode to framework

... I'm not sure how I got that output. Rerunning it shows that the source files were missed:

% git fetch upstream pull/8344/head && git checkout --detach FETCH_HEAD && grep -r 'opmode' . && find . -path '*opmode*'
From https://github.com/wpilibsuite/allwpilib
 * branch                  refs/pull/8344/head -> FETCH_HEAD
HEAD is now at 3566b71202 Move robot base classes from opmode to framework
Binary file ./.gradle/8.14.3/nativeCompile/nativeCompile.bin matches
Binary file ./.gradle/8.14.3/executionHistory/executionHistory.bin matches
./wpilibc/src/main/native/cpp/opmode
./wpilibc/src/main/native/cpp/opmode/RobotState.cpp
./wpilibc/src/main/native/cpp/opmode/TimesliceRobot.cpp
./wpilibc/src/main/native/cpp/opmode/TimedRobot.cpp
./wpilibc/src/main/native/cpp/opmode/IterativeRobotBase.cpp