Knights of Tezoth

How much does one have to abandon dignity and conscience while serving Carneia?

In terms of conscience, you must be prepared to carry out the most brutal orders. As for dignity, it depends more on luck and caution; if you're lucky enough not to trigger anything, you can get through your entire "career" without any incidents.

Does the ritual of being dubbed a Knight involve kissing a boot or some similar humiliating ceremony?

Chaos and randomness prevail over customs with her; it could be a boot, some kind of foolishness, or some act of cruelty—basically, you can describe in your quente how it happened, but it's better to check with me.

How bold can one behave toward her without consequences?

Depends on what mood she is in. But you must always know your place.

Like, could she order a wife to be given to other Knights for "entertainment"?

She could do that if there's a reason (you fail a quest, for example), provided she believes you have very good romantic relations with her. If it's just a static spouse, she wouldn't even think about it. In general, she loves to strike where it hurts most.

Or order servants to be tortured because they poured 2 grams too little wine into a glass?

If she broke a nail that day, then maybe. And not 2, of course, but something more noticeable.