Mark long-deprecated and unused constants for removal

[nburnwal09]

There are few constants in PDE that have been deprecated for a long time and are no longer referenced within the codebase.
This change adds Deprecated tags for those to indicate their planned removal in a future release.

[github-actions]

Test Results

  623 files   -   148    623 suites   - 148   52m 13s ⏱️ - 3m 45s
3 648 tests ±    0  3 593 ✅  -     1   54 💤 ± 0  1 ❌ +1 
8 213 runs   - 2 665  8 073 ✅  - 2 642  139 💤  - 24  1 ❌ +1 

For more details on these failures, see this check.

Results for commit 2c70539. ± Comparison against base commit abc3cc7.

♻️ This comment has been updated with latest results.

[eclipse-pde-bot]

This pull request changes some projects for the first time in this development cycle.
Therefore the following files need a version increment:

ui/org.eclipse.pde.launching/META-INF/MANIFEST.MF

An additional commit containing all the necessary changes was pushed to the top of this PR's branch. To obtain these changes (for example if you want to push more changes) either fetch from your fork or apply the git patch.

Git patch

From c3f98e5e356d8219038e372196e3ff6420e76f54 Mon Sep 17 00:00:00 2001
From: Eclipse PDE Bot <pde-bot@eclipse.org>
Date: Mon, 1 Dec 2025 12:12:34 +0000
Subject: [PATCH] Version bump(s) for 4.39 stream


diff --git a/ui/org.eclipse.pde.launching/META-INF/MANIFEST.MF b/ui/org.eclipse.pde.launching/META-INF/MANIFEST.MF
index 45e9365482..4d331f7d01 100644
--- a/ui/org.eclipse.pde.launching/META-INF/MANIFEST.MF
+++ b/ui/org.eclipse.pde.launching/META-INF/MANIFEST.MF
@@ -2,7 +2,7 @@ Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-Name: %name
 Bundle-SymbolicName: org.eclipse.pde.launching;singleton:=true
-Bundle-Version: 3.13.600.qualifier
+Bundle-Version: 3.13.700.qualifier
 Bundle-RequiredExecutionEnvironment: JavaSE-17
 Bundle-Vendor: %provider-name
 Require-Bundle: org.eclipse.jdt.junit.core;bundle-version="[3.6.0,4.0.0)",
-- 
2.51.2

Further information are available in Common Build Issues - Missing version increments.