Fix read-only open semantics, Studio prompt localization, and multi-process config docs

[Copilot]

Opening a DB in read-only mode could still fail with file lock/denied errors because the storage layer opened files as read-write/create regardless of requested access. In parallel, Studio shipped with hardcoded Italian UI strings, and docs referenced a stale multi-process flag name.

• Storage: honor read-only access at file-open time

  • PageFile.Open() now derives FileMode/FileAccess from PageFileConfig.Access.
  • MemoryMappedFileAccess.Read opens existing files as read-only (FileMode.Open, FileAccess.Read) instead of OpenOrCreate + ReadWrite.

• Studio: align runtime open behavior with selected access mode

  • Encrypted open path now propagates Access = Read when “Read only” is selected.
  • Prevents Studio from implicitly requesting write access during read-only sessions.

• Studio UI text: remove hardcoded Italian prompts

  • File picker title/labels updated to English (Open BLite database, All files).
  • Error prefix standardized from Errore: to Error:.

• Docs: correct multi-process flag name

  • Updated examples and references from EnableMultiProcessAccess to AllowMultiProcessAccess in current and preview READMEs.

• Focused regression coverage

  • Added tests for read-only reader + writer coexistence in multi-process mode.
  • Added test ensuring read-only PageFile open does not create missing DB files.

var writerConfig = PageFileConfig.Default with { AllowMultiProcessAccess = true };
var readerConfig = writerConfig with { Access = MemoryMappedFileAccess.Read };

using var writer = new StorageEngine("shared.db", writerConfig);
using var reader = new StorageEngine("shared.db", readerConfig); // opens concurrently as true read-only

[mrdevrobot]

@copilot review

[Copilot]

@copilot review

Reviewed the latest PR state. CI run status was checked, targeted tests/builds passed locally for the touched areas, and I did not find additional changes needed at this time.

[Copilot]

Pull request overview

This PR tightens BLite’s read-only semantics end-to-end (core storage + Studio) to avoid unintended read/write file opens that can trigger lock/permission failures, while also cleaning up Studio UI prompts and correcting multi-process configuration docs. It also adds focused regression tests around multi-process reader/writer coexistence and read-only “no-create” behavior.

Changes:

• Core: PageFile.Open() now derives FileMode/FileAccess from PageFileConfig.Access (read-only opens existing files read-only).
• Studio: propagates selected access mode during open (including encrypted path) and standardizes UI strings to English.
• Tests/Docs: adds regression coverage for read-only + multi-process scenarios and updates READMEs to use AllowMultiProcessAccess.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tools/BLite.Studio/Views/MainWindow.axaml.cs	Updates file picker title/labels and removes hardcoded Italian UI text.
tools/BLite.Studio/ViewModels/MainWindowViewModel.cs	Threads selected read-only vs read/write access into open configuration and standardizes error prefix.
tests/BLite.Tests/MultiProcessAccessConfigTests.cs	Adds regression tests for read-only reader alongside writer and for read-only open not creating missing files.
src/BLite.Core/Storage/PageFile.cs	Makes file open mode/access honor PageFileConfig.Access to support true read-only opens.
README.md	Fixes documentation to reference AllowMultiProcessAccess.
README-5.0.0-preview.0.md	Fixes documentation to reference AllowMultiProcessAccess.

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