Resolves Gradle deprecation and language version warnings
```gradle
Java compiler version 21 has deprecated support for compiling with source/target version 8.
```
The `java.toolchain.languageVersion` syntax is a superset that covers the previous syntax `android.compileOptions`
Refactor the publish action for Android to ensure that symbols are
published to Sentry for any 'release' buildLevel -- test releases and
alpha/beta/stable releases.
Splits the publish action into `publish-symbols` and
`publish-play-store` so that they can be run separately as needed, as
symbols can be published for test builds, but play store is only touched
for actual releases.
Note: examining the build logs and Sentry server state, it looks like
the publish to Sentry has not been happening for quite a while, so this
commit refactors the Sentry publishing code and establishes the
fv-keyboards publish target also.
Fixes: #14284
Build-bot: release
Test-bot: skip
Removes a number of unused functions from the file, renames remaining
functions to match our builder script prefix patterns, removes unused
imports from various build scripts (e.g. Android).
Fixes: #14453
Clarifies the confusing builder.inc.sh / build-utils.sh distinction by
giving the scripts more appropriate names. Most build scripts should use
builder-full.inc.sh; some helper scripts can use builder-basic.inc.sh.
Documented in resources/build/README.md.
Renames:
* resources/build/builder.inc.sh to resources/build/builder-full.inc.sh
* resources/build/build-utils.sh to resources/build/builder-basic.inc.sh
Other changes:
* Moves Android-specific functions out of builder-basic.inc.sh and into
android/build.sh.
* Renames functions in builder-basic.inc.sh
More functions may be moved from builder-basic.inc.sh into utils.inc.sh
or other scripts in the future.
Fixes: #14065
Build-bot: build all
Test-bot: skip
Adds documentation for various functions, removes unused functions (a
couple of simple, very lightly used functions were unDRYed; these could
go back the other way across all shell scripts if necessary). TODO items
noted for follow-up refactoring.
Fixes: #14275
Relates-to: #14269
Build-bot: build all
Test-bot: skip
Previously the builder scripts defined a readonly `VERSION` environment
variable for the Keyman version. That caused problems when another
(external) script tried to define a `VERSION` variable. We encountered
this problem when trying to move the TC build steps of a configuration
into a single script (#13399) when we tried to source `~/.nvm/nvm.sh`.
This change uses a Keyman specific prefix for the version variables and
renames `VERSION` → `KEYMAN_VERSION` etc. Unfortunately these variables
are used in a lot of places, so this turned out to be a bit of a yak
shave.
Test-bot: skip
From the days of stable-12.0 when the FirstVoices for Android app was configured in the main repo, the SystemKeyboard initialized with
3148aa7b8c/oem/firstvoices/android/app/src/main/java/com/firstvoices/keyboards/SystemKeyboard.java (L111-L113)
In the scenario FV for Android installed and enabled as the system keyboard (from the Android settings menu instead of launching the FV app), the initial usage as a system keyboard would have an uninitialized keyboard key (language and keyboard ID pairing to determine the current keyboard).
Fixes: FV-ANDROID-5G
Fixes: FV-ANDROID-7N
