Adds Mississippi River map - vertical pipe map

[RickD004]

Resolves #4153

Description:

Add Mississippi river, inspired by Amazon, but vertical. Pipe-type map along Amazon and Passage. 11 nations, with 51 additional nations for a total of 62 for Humans vs Nations gamemode.

mississippi62nations.mp4

mississippiteaser.mp4

mississippiteaser2.mp4

Please complete the following:

• I have added screenshots for all UI updates
• I process any text displayed to the user through translateText() and I've added it to the en.json file
• I have added relevant tests to the test directory

Please put your Discord username so you can be contacted if a bug or regression is found:

tri.star1011

[coderabbitai]

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ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: c20f8961-2d34-410d-a6db-28212c536d43

📥 Commits

Reviewing files that changed from the base of the PR and between 385b4dd and 62a799d.

⛔ Files ignored due to path filters (4)

• map-generator/assets/maps/mississippiriver/image.png is excluded by !**/*.png
• resources/maps/mississippiriver/map.bin is excluded by !**/*.bin
• resources/maps/mississippiriver/map16x.bin is excluded by !**/*.bin
• resources/maps/mississippiriver/map4x.bin is excluded by !**/*.bin

📒 Files selected for processing (7)

• map-generator/assets/maps/mississippiriver/info.json
• map-generator/main.go
• resources/lang/en.json
• resources/maps/mississippiriver/manifest.json
• resources/maps/mississippiriver/thumbnail.webp
• src/core/game/Game.ts
• src/server/MapPlaylist.ts

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Walkthrough

Adds the Mississippi River regional map to the game by introducing map metadata (geometry and nation placements), registering a new GameMapType.MississippiRiver enum value, integrating it into the regional category, and wiring it into the map generator and playlist rotation with localization support.

Changes

Mississippi River Map Addition

Layer / File(s)	Summary
Map Content and Metadata map-generator/assets/maps/mississippiriver/info.json, resources/maps/mississippiriver/manifest.json	New assets define the Mississippi River map with 11 nations (named with coordinates and flags) and 51 additional nations for placement. Manifest specifies map dimensions and tile counts for the base and scaled variants.
Game Type and Category Registration src/core/game/Game.ts	GameMapType enum gains MississippiRiver member, and it is added to the mapCategories.regional list so the map appears in game mode and selection logic.
Map Generation Registry and Runtime Wiring map-generator/main.go, resources/lang/en.json, src/server/MapPlaylist.ts	Map is registered in the generator, localization key added for the map name, and playlist frequency weight set to 3 for weighted selection in game rotation.

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Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~3 minutes

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Possibly related PRs

• openfrontio/OpenFrontIO#4143: Both PRs add new map support by extending the same code paths (new map ID in map-generator/main.go, new GameMapType enum value and category wiring in src/core/game/Game.ts, and new playlist weighting entries in src/server/MapPlaylist.ts) alongside corresponding manifest/locale assets.
• openfrontio/OpenFrontIO#3998: Both PRs add a new regional map by updating the same core integration points—Game.ts (GameMapType enum + mapCategories.regional) and src/server/MapPlaylist.ts (FREQUENCY entry)—along with the corresponding map registry/localization/manifest data.
• openfrontio/OpenFrontIO#3975: Both PRs add a new regional map end-to-end—registering it in map-generator/main.go, adding map metadata/manifest/info.json, extending GameMapType + mapCategories in src/core/game/Game.ts, and updating playlist weights in src/server/MapPlaylist.ts (plus the corresponding resources/lang/en.json key).

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Suggested labels

bypass-pr-check

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Suggested reviewers

• evanpelle

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Poem

🌊 Down the Mississippi, a map takes its flow,
Eleven proud nations in a vertical row,
With fifty-one neighbors along the great bend,
A regional treasure for players to spend! 🎮

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately describes the main change: adding a Mississippi River map that is vertical and pipe-type in style.
Description check	✅ Passed	The description is directly related to the changeset, referencing issue #4153, explaining the map type, nation count, and confirming completion of required tasks.
Linked Issues check	✅ Passed	The pull request implements all coding requirements from issue #4153: adds Mississippi River map metadata with 11 nations and 51 additional nations, registers it in the map system, adds localization entries, and includes necessary configuration updates.
Out of Scope Changes check	✅ Passed	All changes are within scope: map asset definitions, game enum updates, map registration, playlist weights, and localization entries directly support adding the Mississippi River map.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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Warning

There were issues while running some tools. Please review the errors and either fix the tool's configuration or disable the tool if it's a critical failure.

🔧 golangci-lint (2.12.2)

level=error msg="[linters_context] typechecking error: pattern ./...: directory prefix . does not contain main module or its selected dependencies"

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