chore: replace config files (#25)

## Explanation

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Change config files extensions. 
Align snap's tsconfig, preserve compiler flags enabled in the snap.
Adjust sample tsconfig  

## References

Related to
[WPN-1320](https://consensyssoftware.atlassian.net/browse/WPN-1320)

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## Checklist

- [ ] I've updated the test suite for new or updated code as appropriate
- [ ] I've updated documentation (JSDoc, Markdown, etc.) for new or
updated code as appropriate
- [ ] I've communicated my changes to consumers by [updating changelogs
for packages I've
changed](https://github.com/MetaMask/core/tree/main/docs/processes/updating-changelogs.md)
- [ ] I've introduced [breaking
changes](https://github.com/MetaMask/core/tree/main/docs/processes/breaking-changes.md)
in this PR and have prepared draft pull requests for clients and
consumer packages to resolve them

Author: taran-a

…kages/bitcoin-wallet-snap/jest.config.js …ages/bitcoin-wallet-snap/jest.config.mjsmerged-packages/bitcoin-wallet-snap/jest.config.js renamed to merged-packages/bitcoin-wallet-snap/jest.config.mjs merged-packages/bitcoin-wallet-snap/jest.config.js renamed to merged-packages/bitcoin-wallet-snap/jest.config.mjs

@@ -1,10 +1,15 @@
 {
   "extends": "../../tsconfig.packages.json",
   "compilerOptions": {
+    "baseUrl": "./",
     "resolveJsonModule": true /*  lets us import JSON modules from within TypeScript modules. */,
     "jsx": "react-jsx",
     "jsxImportSource": "@metamask/snaps-sdk",
     "exactOptionalPropertyTypes": false,
+    "forceConsistentCasingInFileNames": true,
+    "noErrorTruncation": true,
+    "noUncheckedIndexedAccess": true,
+    "skipLibCheck": true,
     "types": ["jest"]
   },
   "include": ["**/*.ts", "**/*.tsx", "locales/*.json"]

…n-wallet-snap/jest.integration.config.js …-wallet-snap/jest.integration.config.mjsmerged-packages/bitcoin-wallet-snap/jest.integration.config.js renamed to merged-packages/bitcoin-wallet-snap/jest.integration.config.mjs merged-packages/bitcoin-wallet-snap/jest.integration.config.js renamed to merged-packages/bitcoin-wallet-snap/jest.integration.config.mjs

@@ -1,10 +1,10 @@
 {
-  "extends": "../../tsconfig.json",
+  "extends": "../../tsconfig.packages.json",
   "compilerOptions": {
     "baseUrl": "./",
     "jsx": "react-jsx",
     "jsxImportSource": "@metamask/snaps-sdk",
     "types": ["jest"]
   },
-  "include": ["**/*.ts", "**/*.tsx"]
+  "include": ["**/*.ts", "**/*.tsx", "locales/*.json"]
 }