flatten modules to repo root, vendor deps, repair Eclipse build paths

Move api, engine, ui-console and ui-desktop out of modules/ up to the
repo root and drop the empty exception project (GuessMarketException now
lives in api).

Vendor gson, jaxb, okhttp, openjfx and tomcat under lib/, and group the
JUnit standalone jar into lib/junit/ alongside them.

Rewrite every .classpath: drop the copy-pasted optional="true" that was
masking real build path errors, point the library entries at ../lib/,
and put the JUnit jar on the test source folders so the placeholder
AppTest classes compile.

ui-desktop: take the JavaFX jars off the modulepath (there is no
module-info.java, so module="true" left the packages unresolvable) and
add a Launcher that calls Application.launch, avoiding the "JavaFX
runtime components are missing" check without VM arguments.

engine: add LocalGuessMarketService and the GuessMarketContext provider
interface, and give GuessMarketException the no-arg and cause
constructors they need.

1 files changed, 3 insertions, 0 deletions

diff --git a/lib/openjfx/javafx.properties b/lib/openjfx/javafx.properties
new file mode 100644
index 0000000..bfea014
--- /dev/null
+++ b/lib/openjfx/javafx.properties
@@ -0,0 +1,3 @@
+javafx.version=22.0.2
+javafx.runtime.version=22.0.2+4
+javafx.runtime.build=4