Bump to v0.1.2 with About-tab rebrand and Hellion-style README

Manifest moves to 0.1.2.0 so existing testers get an in-place
update offer once the matching GitHub release is published.

Changes since 0.1.1 are surface and packaging:

  - The inherited About tab now reflects the fork: Hellion Online
    Media as maintainer with hellion-media.de as the contact
    channel, EUPL-1.2 dual-copyright statement, FINAL FANTASY XIV
    SQUARE ENIX disclaimer, explicit acknowledgment of Chat 2 by
    Infi & Anna as the upstream foundation, and the original
    ChatTwo translator list relabelled as upstream Crowdin
    contributors so it isn't mistaken for Hellion translators.
  - Cherry-picked the upstream DBViewer UI improvements
    (auto-scroll-reset on page change, localized tooltips on the
    date reset, folder export, export-running notifications and
    the pagination arrows).
  - README rewritten in the Hellion project style: German prose,
    tech-stack table, architecture tree, database column list, a
    proper migration guide for users coming from Chat 2 (with
    Linux and Windows manual recovery commands), upstream-sync
    workflow notes for cherry-picks, project-status checklist
    separating bootstrap-done from phase-2-open work, and the
    Hellion Online Media footer.
  - repo.json regenerated to point at the v0.1.2 GitHub release
    asset URL.

Bundle changelog summarises the same so testers see the new
content in their plugin list before they pull the update.

ChatTwo/ChatTwo.csproj

@@ -4,7 +4,7 @@
              0.1.0 is our bootstrap release; the underlying Chat 2 base is
              called out in the yaml changelog so users can see what it
              derives from. -->
-        <Version>0.1.1</Version>
+        <Version>0.1.2</Version>
         <ImplicitUsings>enable</ImplicitUsings>
         <!-- HellionChat fork: assembly is renamed so Dalamud uses
              pluginConfigs/HellionChat instead of pluginConfigs/ChatTwo,

ChatTwo/HellionChat.yaml

@@ -37,6 +37,22 @@ tags:
   - Replacement
   - Privacy
 changelog: |-
+  **Hellion Chat 0.1.2 — About tab rebrand, DBViewer polish**
+
+  - About tab now shows Hellion-specific maintainer, license, EU/US/JP
+    disclaimer and SQUARE ENIX disclaimer instead of the inherited
+    Chat 2 contact info; original ChatTwo translator credits stay
+    visible under a clearly labelled upstream tree node
+  - Localization clarified: Hellion-specific German strings are
+    maintained by the fork maintainer, the Crowdin contributor list
+    only covers the inherited upstream strings
+  - Cherry-picked DBViewer UI improvements from upstream Chat 2
+    (auto-scroll-reset on page change, tooltips on date reset,
+    folder export, page arrows, localized export-running messages)
+  - README rewritten in the Hellion project style with a tech-stack
+    table, architecture tree, database column list, install guide,
+    upstream-sync workflow notes and project-status checklist
+
   **Hellion Chat 0.1.1 — Packaging and migration fixes**
 
   - Plugin icon now ships inside the bundle, so the Hellion logo