slice_and_print

        ``version_id`` / ``design_id`` / ``branch_id`` name the kept design
        this file came from, when there is one: the print's record then
        lands on that version's history (what printed, on which machine,
        how it ended) instead of on a bare file name.  A file that is
        not a Kiln design passes none and is recorded by file alone.
        ``account_sync_id`` is the id the print's record already has on
        the person's Kiln account, when the door that sent the print
        opened it there first; agents leave it unset.

        Colour is a promise kept here.  A part made in a colour (the
        ``color`` the make was asked for, or the one its source named)
        prints from a loaded spool of that colour: on a printer with an
        AMS the slot is chosen and named in the result; with none of that
        colour loaded the print is HELD (``code: "COLOR_NOT_LOADED"``),
        naming the nearest loaded spool, so the person decides before
        anything prints -- call again with ``color="<that colour>"`` to
        print in it, or load the asked colour and call again; on a
        printer with no unit Kiln can read it prints in whatever is
        loaded and the result says so.  ``color`` here overrides the
        make's: a colour word or hex to print in instead, or ``"any"``
        to print in whatever is loaded.

        For a more comprehensive pipeline with validation and profile auto-detection,
        use ``run_quick_print``. For custom slicer overrides, use ``run_reslice_and_print``.
        Automatically analyzes bed adhesion and adds brim/raft when needed
        based on model geometry, material warp tendency, and printer type.
        This adhesion intelligence only activates when no custom profile is
        supplied; when it could not read the model, ``printability_note``
        says why.  A skirt that would print past the edge of the bed is
        dropped and the part sliced again; a brim that would is refused
        with the width that fits.

        Pre-print validation gate: mesh inputs (.stl/.obj/.3mf/.step/.glb)
        run through Kiln's full validation pipeline before slicing —
        format check, watertight check, auto-repair, printability scoring
        (0-100), bed-fit, and material checks.  Designs that fail the gate
        are blocked before reaching the printer; auto-repaired meshes are
        sliced from the repaired path.  Pass ``skip_validation=True`` to
        bypass (e.g. for already-validated meshes or pre-sliced 3MFs).

        Args:
            input_path: Path to the 3D model file (STL, 3MF, STEP, etc.).
            printer_name: Target printer name.  Omit for the default printer.
            profile: Path to a slicer profile/config file.
            printer_id: Optional printer model ID for bundled profile
                auto-selection (e.g. ``"prusa_mini"``).
            material: Filament material (e.g. ``"PLA"``, ``"ABS"``).  It
                sets the slice's temperatures, melt rate and cooling
                (``build_material_overrides`` shows them), its density
                weighs the print, and it steers the automatic brim/raft
                decision.  Omitted, the spool the printer reports loaded
                answers, then PLA — the response's ``slice.filament``
                says which.
            metadata: Optional pass-through fields for a printable
                assembly manual made beside the print.  Recognised keys
                (all optional): ``assembly_json``, ``manual_output_dir``,
                ``manual_design_name``, ``manual_branding``,
                ``manual_co_brand_name``, ``manual_languages``,
                ``manual_cover_language``.  The manual, when one is
                made, is returned under ``assembly_manual``; keys a plan
                does not include are accepted and ignored.
            skip_validation: Bypass the pre-print validation gate.
                Defaults to False — designs are pre-tested for
                printability before they reach the printer.  Set to
                True only when the caller has already validated the
                mesh (e.g. ``validate_and_prepare`` was just called)
                or when the input is a pre-sliced 3MF the validator
                can't introspect.
            placement: Where the part goes when the plate still holds the
                last print: ``[x, y]`` in mm (the part's footprint
                origin), a named region (``"front-left"``, ``"centre"``,
                ``"back-right"``, …), or ``"keep"``.  Omitted, an
                occupied plate refuses before anything is sliced and
                lists the spots that would work; a clear plate prints as
                before.  The response's ``placement`` block is the
                clearance verdict, checked again on the sliced file
                before upload.  The clearance verdict is always given;
                placing and starting a second print on an occupied
                plate is included where the plan carries it.
            hardware: Bought parts that go into the part while it
                prints, as short phrases such as ``["4x 6x3 magnet",
                "2x M3 nut"]``.  The file that prints carries the pause
                Kiln's servers wrote into it, and the response's
                ``hardware`` block says what goes in and when; a part
                that needs a pause that cannot be written is refused
                before anything is sent to the printer.  Left out, a
                part with a pocket that would be sealed inside the
                print is refused with ``HARDWARE_UNNAMED`` and the
                planner's question for each pocket ("this hex pocket
                takes an M3 nut -- right?"): ask the person, then call
                again with what they said, or ``["none"]`` to print
                every pocket empty on their word.  ``["none"]`` with a
                pause already in the sliced file over a sealed pocket
                is refused as a contradiction (``HARDWARE_NONE_BUT_PAUSED``).
                The pause is written where the plan carries it.
            auto_center: Centre the model on the plate before slicing
                (default ``True``).  ``False`` keeps the model where its
                file places it.
            preview_token: Token from ``issue_preview_token`` proving this
                model was shown to the person before printing.  Required
                beside their go-ahead: a print is shown to its owner
                before it starts.
            color: The colour to print in, overriding the make's: a colour
                word or hex, or ``"any"`` to print in whatever is loaded.
                Omitted, the colour the part was made in is matched to a
                loaded spool, or the print is held.
            version_id: The kept design version this file came from, so
                the print's record lands on that version's history.  A
                file that is not a Kiln design passes none.
            design_id: The design that version belongs to; passed with
                ``version_id``.
            branch_id: The branch that version is on; passed with
                ``version_id``.
            account_sync_id: The id the print's record already has on the
                person's Kiln account, when the door that sent the print
                opened it there first.  Agents leave it unset.

        Combines ``slice_model``, ``upload_file``, and ``start_print`` into
        a single action.

        Branch on ``print_start`` — one field, three values, and the
        nested ``print`` block carries the identical pair so the two
        halves cannot disagree:

        - ``"started"``: the printer, asked after the command, is printing.
        - ``"accepted"``: the command was sent and not refused, and the
          machine has not confirmed it is running.  Normal during the
          start-up transient (homing, AMS load, calibration).  Call
          ``printer_status()`` to watch it start.
        - ``"failed"``: the printer, asked after the command, is idle or
          errored — it did not take the job.

        ``success`` is ``False`` only for ``"failed"``.