feat(drivers/mediafire): support concurrent upload

[ILoveScratch2]

Reopened #1366

[KirCute]

咱们自己改的话，我觉得不如直接合并，然后后续工作都在#1322 进行

[Copilot]

Pull Request Overview

This PR implements concurrent upload support for the MediaFire driver, transforming sequential unit uploads into parallel processing for improved performance. The changes include adding thread-safe upload operations, intelligent buffer sizing, and automatic session token renewal.

• Replaces sequential upload loop with concurrent processing using ordered groups and retry logic
• Adds configurable upload thread count and intelligent buffer sizing based on file size
• Implements automatic session token renewal with randomized intervals to prevent expiry

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
internal/stream/util.go	Adds DiscardSection method for skipping data sections in stream processing
drivers/mediafire/util.go	Major refactor to implement concurrent upload with thread-safe operations and retry logic
drivers/mediafire/meta.go	Adds UploadThreads configuration parameter for concurrent upload control
drivers/mediafire/driver.go	Implements automatic session token renewal with randomized cron scheduling
README_nl.md	Updates documentation to include MediaFire in supported storage providers list

Comments suppressed due to low confidence (2)

drivers/mediafire/util.go:1

• [nitpick] The comment has a formatting issue with '(6- 9)' - it should be '(6-9)' without the extra space.

package mediafire

drivers/mediafire/util.go:1

• [nitpick] The comment 'Crazy, but working way' is unprofessional and doesn't explain why this approach is necessary. Consider replacing with a more descriptive explanation of the token refresh strategy.

package mediafire

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[Copilot]

The context ctx from Init method is captured in the cron closure, but this context may be canceled or expired when the cron job runs later. The cron job should use a background context or create a new context for token renewal.

Suggested change

	d.renewToken(ctx)
	d.renewToken(context.Background())

[Copilot]

The error returned by d.renewToken(ctx) is ignored. If token renewal fails, the Init method should return the error instead of continuing execution.

Suggested change

	d.renewToken(ctx)
	if err := d.renewToken(ctx); err != nil {
	return fmt.Errorf("Init :: [MediaFire] failed to renew token: %w", err)
	}

[Da3zKi7]

@KirCute @ILoveScratch2

Now confusion is solved, if you need something, just ask me. I found out you are good mates.