feat(filesystems/swap): add discardPolicy, finit-managed randomEncryption, and boot.resumeDevice

[FixeQD]

Ported standard NixOS swap and hibernation options to work seamlessly within the finix architecture, replacing systemd components with native finit configuration

Changes:

1. Swap Discard Policy: Backported the swapDevices.*.discardPolicy option (once, pages, both), mapping it correctly to standard swap mount options
2. Finit-Managed Random Encryption: Reimplemented NixOS-style random swap encryption without relying on systemd-cryptsetup targets. Instead of using static /etc/fstab lines, encrypted swaps are now generated imperatively via dedicated stage-1 finit.tasks. The tasks execute a lightweight script shell sequence on every boot.Added an assertion to ensure these devices use stable persistent paths rather than volatile labels or UUIDs
3. Hibernation Support: Added the boot.resumeDevice option to inject the resume= string into boot.kernelParams

[Copilot]

Pull request overview

This PR ports several NixOS swap/hibernation-related options into finix, adapting them to finix’s finit-based boot architecture (including imperative swap setup for random-encrypted swap).

Changes:

• Add swapDevices.*.discardPolicy and map it to swap options (discard, discard=once|pages).
• Add swapDevices.*.randomEncryption and create finit-managed encrypted swap tasks instead of generating static /etc/fstab swap entries.
• Add boot.resumeDevice and inject resume=<device> into boot.kernelParams.

Reviewed changes

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

File	Description
modules/filesystems/options.nix	Adds new swap options (discardPolicy, randomEncryption) to the swap device option schema.
modules/filesystems/default.nix	Implements discard policy mapping and adds finit tasks + assertions for random-encrypted swap handling.
modules/boot/kernel.nix	Introduces boot.resumeDevice and conditionally adds resume= to the kernel cmdline.

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