Prepare PraetorisClient 0.1.106 with Endgame 0.8.0 #150

Prepare PraetorisClient 0.1.106 with bundled Valheim Endgame 0.8.0 for Thunderstore review.

• The published 0.1.105 package bundles Endgame 0.7.0. Its source is commit 62fedd4; the corresponding source PR Prepare PraetorisClient 0.1.105 with Endgame 0.7.0 #149 is still open.
• Update plugin, assembly, manifest, and Thunderstore version metadata. Preserve the shipped gameplay source and existing package dependencies.
• Build both DLLs, update staged release notes and the stale bundled Endgame version in the package README, and verify archive contents, assembly versions, icon dimensions, and checksums against 0.1.105.
• Endgame live validation and unresolved observations are documented at https://github.com/jneb802/ValheimEndgame/issues/133#issuecomment-6379291809 and https://github.com/jneb802/ValheimEndgame/issues/142 .
• Keep Endgame bundled. Do not publish or deploy as part of this preparation task.